net/batman-adv/translation-table.c

   1 /* Copyright (C) 2007-2013 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 /* hash class keys */
  33 static struct lock_class_key batadv_tt_local_hash_lock_class_key;
  34 static struct lock_class_key batadv_tt_global_hash_lock_class_key;
  35
  36 static void batadv_send_roam_adv(struct batadv_priv *bat_priv, uint8_t *client,
  37                                  struct batadv_orig_node *orig_node);
  38 static void batadv_tt_purge(struct work_struct *work);
  39 static void
  40 batadv_tt_global_del_orig_list(struct batadv_tt_global_entry *tt_global_entry);
  41 static void batadv_tt_global_del(struct batadv_priv *bat_priv,
  42                                  struct batadv_orig_node *orig_node,
  43                                  const unsigned char *addr,
  44                                  const char *message, bool roaming);
  45
  46 /* returns 1 if they are the same mac addr */
  47 static int batadv_compare_tt(const struct hlist_node *node, const void *data2)
  48 {
  49         const void *data1 = container_of(node, struct batadv_tt_common_entry,
  50                                          hash_entry);
  51
  52         return (memcmp(data1, data2, ETH_ALEN) == 0 ? 1 : 0);
  53 }
  54
  55 static struct batadv_tt_common_entry *
  56 batadv_tt_hash_find(struct batadv_hashtable *hash, const void *data)
  57 {
  58         struct hlist_head *head;
  59         struct batadv_tt_common_entry *tt_common_entry;
  60         struct batadv_tt_common_entry *tt_common_entry_tmp = NULL;
  61         uint32_t index;
  62
  63         if (!hash)
  64                 return NULL;
  65
  66         index = batadv_choose_orig(data, hash->size);
  67         head = &hash->table[index];
  68
  69         rcu_read_lock();
  70         hlist_for_each_entry_rcu(tt_common_entry, head, hash_entry) {
  71                 if (!batadv_compare_eth(tt_common_entry, data))
  72                         continue;
  73
  74                 if (!atomic_inc_not_zero(&tt_common_entry->refcount))
  75                         continue;
  76
  77                 tt_common_entry_tmp = tt_common_entry;
  78                 break;
  79         }
  80         rcu_read_unlock();
  81
  82         return tt_common_entry_tmp;
  83 }
  84
  85 static struct batadv_tt_local_entry *
  86 batadv_tt_local_hash_find(struct batadv_priv *bat_priv, const void *data)
  87 {
  88         struct batadv_tt_common_entry *tt_common_entry;
  89         struct batadv_tt_local_entry *tt_local_entry = NULL;
  90
  91         tt_common_entry = batadv_tt_hash_find(bat_priv->tt.local_hash, data);
  92         if (tt_common_entry)
  93                 tt_local_entry = container_of(tt_common_entry,
  94                                               struct batadv_tt_local_entry,
  95                                               common);
  96         return tt_local_entry;
  97 }
  98
  99 static struct batadv_tt_global_entry *
 100 batadv_tt_global_hash_find(struct batadv_priv *bat_priv, const void *data)
 101 {
 102         struct batadv_tt_common_entry *tt_common_entry;
 103         struct batadv_tt_global_entry *tt_global_entry = NULL;
 104
 105         tt_common_entry = batadv_tt_hash_find(bat_priv->tt.global_hash, data);
 106         if (tt_common_entry)
 107                 tt_global_entry = container_of(tt_common_entry,
 108                                                struct batadv_tt_global_entry,
 109                                                common);
 110         return tt_global_entry;
 111 }
 112
 113 static void
 114 batadv_tt_local_entry_free_ref(struct batadv_tt_local_entry *tt_local_entry)
 115 {
 116         if (atomic_dec_and_test(&tt_local_entry->common.refcount))
 117                 kfree_rcu(tt_local_entry, common.rcu);
 118 }
 119
 120 static void batadv_tt_global_entry_free_rcu(struct rcu_head *rcu)
 121 {
 122         struct batadv_tt_common_entry *tt_common_entry;
 123         struct batadv_tt_global_entry *tt_global_entry;
 124
 125         tt_common_entry = container_of(rcu, struct batadv_tt_common_entry, rcu);
 126         tt_global_entry = container_of(tt_common_entry,
 127                                        struct batadv_tt_global_entry, common);
 128
 129         kfree(tt_global_entry);
 130 }
 131
 132 static void
 133 batadv_tt_global_entry_free_ref(struct batadv_tt_global_entry *tt_global_entry)
 134 {
 135         if (atomic_dec_and_test(&tt_global_entry->common.refcount)) {
 136                 batadv_tt_global_del_orig_list(tt_global_entry);
 137                 call_rcu(&tt_global_entry->common.rcu,
 138                          batadv_tt_global_entry_free_rcu);
 139         }
 140 }
 141
 142 static void batadv_tt_orig_list_entry_free_rcu(struct rcu_head *rcu)
 143 {
 144         struct batadv_tt_orig_list_entry *orig_entry;
 145
 146         orig_entry = container_of(rcu, struct batadv_tt_orig_list_entry, rcu);
 147
 148         /* We are in an rcu callback here, therefore we cannot use
 149          * batadv_orig_node_free_ref() and its call_rcu():
 150          * An rcu_barrier() wouldn't wait for that to finish
 151          */
 152         batadv_orig_node_free_ref_now(orig_entry->orig_node);
 153         kfree(orig_entry);
 154 }
 155
 156 static void
 157 batadv_tt_orig_list_entry_free_ref(struct batadv_tt_orig_list_entry *orig_entry)
 158 {
 159         if (!atomic_dec_and_test(&orig_entry->refcount))
 160                 return;
 161         /* to avoid race conditions, immediately decrease the tt counter */
 162         atomic_dec(&orig_entry->orig_node->tt_size);
 163         call_rcu(&orig_entry->rcu, batadv_tt_orig_list_entry_free_rcu);
 164 }
 165
 166 /**
 167  * batadv_tt_local_event - store a local TT event (ADD/DEL)
 168  * @bat_priv: the bat priv with all the soft interface information
 169  * @tt_local_entry: the TT entry involved in the event
 170  * @event_flags: flags to store in the event structure
 171  */
 172 static void batadv_tt_local_event(struct batadv_priv *bat_priv,
 173                                   struct batadv_tt_local_entry *tt_local_entry,
 174                                   uint8_t event_flags)
 175 {
 176         struct batadv_tt_change_node *tt_change_node, *entry, *safe;
 177         struct batadv_tt_common_entry *common = &tt_local_entry->common;
 178         uint8_t flags = common->flags | event_flags;
 179         bool event_removed = false;
 180         bool del_op_requested, del_op_entry;
 181
 182         tt_change_node = kmalloc(sizeof(*tt_change_node), GFP_ATOMIC);
 183         if (!tt_change_node)
 184                 return;
 185
 186         tt_change_node->change.flags = flags;
 187         tt_change_node->change.reserved = 0;
 188         memcpy(tt_change_node->change.addr, common->addr, ETH_ALEN);
 189
 190         del_op_requested = flags & BATADV_TT_CLIENT_DEL;
 191
 192         /* check for ADD+DEL or DEL+ADD events */
 193         spin_lock_bh(&bat_priv->tt.changes_list_lock);
 194         list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
 195                                  list) {
 196                 if (!batadv_compare_eth(entry->change.addr, common->addr))
 197                         continue;
 198
 199                 /* DEL+ADD in the same orig interval have no effect and can be
 200                  * removed to avoid silly behaviour on the receiver side. The
 201                  * other way around (ADD+DEL) can happen in case of roaming of
 202                  * a client still in the NEW state. Roaming of NEW clients is
 203                  * now possible due to automatically recognition of "temporary"
 204                  * clients
 205                  */
 206                 del_op_entry = entry->change.flags & BATADV_TT_CLIENT_DEL;
 207                 if (!del_op_requested && del_op_entry)
 208                         goto del;
 209                 if (del_op_requested && !del_op_entry)
 210                         goto del;
 211                 continue;
 212 del:
 213                 list_del(&entry->list);
 214                 kfree(entry);
 215                 kfree(tt_change_node);
 216                 event_removed = true;
 217                 goto unlock;
 218         }
 219
 220         /* track the change in the OGMinterval list */
 221         list_add_tail(&tt_change_node->list, &bat_priv->tt.changes_list);
 222
 223 unlock:
 224         spin_unlock_bh(&bat_priv->tt.changes_list_lock);
 225
 226         if (event_removed)
 227                 atomic_dec(&bat_priv->tt.local_changes);
 228         else
 229                 atomic_inc(&bat_priv->tt.local_changes);
 230 }
 231
 232 int batadv_tt_len(int changes_num)
 233 {
 234         return changes_num * sizeof(struct batadv_tt_change);
 235 }
 236
 237 static int batadv_tt_local_init(struct batadv_priv *bat_priv)
 238 {
 239         if (bat_priv->tt.local_hash)
 240                 return 0;
 241
 242         bat_priv->tt.local_hash = batadv_hash_new(1024);
 243
 244         if (!bat_priv->tt.local_hash)
 245                 return -ENOMEM;
 246
 247         batadv_hash_set_lock_class(bat_priv->tt.local_hash,
 248                                    &batadv_tt_local_hash_lock_class_key);
 249
 250         return 0;
 251 }
 252
 253 static void batadv_tt_global_free(struct batadv_priv *bat_priv,
 254                                   struct batadv_tt_global_entry *tt_global,
 255                                   const char *message)
 256 {
 257         batadv_dbg(BATADV_DBG_TT, bat_priv,
 258                    "Deleting global tt entry %pM: %s\n",
 259                    tt_global->common.addr, message);
 260
 261         batadv_hash_remove(bat_priv->tt.global_hash, batadv_compare_tt,
 262                            batadv_choose_orig, tt_global->common.addr);
 263         batadv_tt_global_entry_free_ref(tt_global);
 264 }
 265
 266 void batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr,
 267                          int ifindex)
 268 {
 269         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 270         struct batadv_tt_local_entry *tt_local;
 271         struct batadv_tt_global_entry *tt_global;
 272         struct hlist_head *head;
 273         struct batadv_tt_orig_list_entry *orig_entry;
 274         int hash_added;
 275         bool roamed_back = false;
 276
 277         tt_local = batadv_tt_local_hash_find(bat_priv, addr);
 278         tt_global = batadv_tt_global_hash_find(bat_priv, addr);
 279
 280         if (tt_local) {
 281                 tt_local->last_seen = jiffies;
 282                 if (tt_local->common.flags & BATADV_TT_CLIENT_PENDING) {
 283                         batadv_dbg(BATADV_DBG_TT, bat_priv,
 284                                    "Re-adding pending client %pM\n", addr);
 285                         /* whatever the reason why the PENDING flag was set,
 286                          * this is a client which was enqueued to be removed in
 287                          * this orig_interval. Since it popped up again, the
 288                          * flag can be reset like it was never enqueued
 289                          */
 290                         tt_local->common.flags &= ~BATADV_TT_CLIENT_PENDING;
 291                         goto add_event;
 292                 }
 293
 294                 if (tt_local->common.flags & BATADV_TT_CLIENT_ROAM) {
 295                         batadv_dbg(BATADV_DBG_TT, bat_priv,
 296                                    "Roaming client %pM came back to its original location\n",
 297                                    addr);
 298                         /* the ROAM flag is set because this client roamed away
 299                          * and the node got a roaming_advertisement message. Now
 300                          * that the client popped up again at its original
 301                          * location such flag can be unset
 302                          */
 303                         tt_local->common.flags &= ~BATADV_TT_CLIENT_ROAM;
 304                         roamed_back = true;
 305                 }
 306                 goto check_roaming;
 307         }
 308
 309         tt_local = kmalloc(sizeof(*tt_local), GFP_ATOMIC);
 310         if (!tt_local)
 311                 goto out;
 312
 313         batadv_dbg(BATADV_DBG_TT, bat_priv,
 314                    "Creating new local tt entry: %pM (ttvn: %d)\n", addr,
 315                    (uint8_t)atomic_read(&bat_priv->tt.vn));
 316
 317         memcpy(tt_local->common.addr, addr, ETH_ALEN);
 318         /* The local entry has to be marked as NEW to avoid to send it in
 319          * a full table response going out before the next ttvn increment
 320          * (consistency check)
 321          */
 322         tt_local->common.flags = BATADV_TT_CLIENT_NEW;
 323         if (batadv_is_wifi_iface(ifindex))
 324                 tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
 325         atomic_set(&tt_local->common.refcount, 2);
 326         tt_local->last_seen = jiffies;
 327         tt_local->common.added_at = tt_local->last_seen;
 328
 329         /* the batman interface mac address should never be purged */
 330         if (batadv_compare_eth(addr, soft_iface->dev_addr))
 331                 tt_local->common.flags |= BATADV_TT_CLIENT_NOPURGE;
 332
 333         hash_added = batadv_hash_add(bat_priv->tt.local_hash, batadv_compare_tt,
 334                                      batadv_choose_orig, &tt_local->common,
 335                                      &tt_local->common.hash_entry);
 336
 337         if (unlikely(hash_added != 0)) {
 338                 /* remove the reference for the hash */
 339                 batadv_tt_local_entry_free_ref(tt_local);
 340                 goto out;
 341         }
 342
 343 add_event:
 344         batadv_tt_local_event(bat_priv, tt_local, BATADV_NO_FLAGS);
 345
 346 check_roaming:
 347         /* Check whether it is a roaming, but don't do anything if the roaming
 348          * process has already been handled
 349          */
 350         if (tt_global && !(tt_global->common.flags & BATADV_TT_CLIENT_ROAM)) {
 351                 /* These node are probably going to update their tt table */
 352                 head = &tt_global->orig_list;
 353                 rcu_read_lock();
 354                 hlist_for_each_entry_rcu(orig_entry, head, list) {
 355                         batadv_send_roam_adv(bat_priv, tt_global->common.addr,
 356                                              orig_entry->orig_node);
 357                 }
 358                 rcu_read_unlock();
 359                 if (roamed_back) {
 360                         batadv_tt_global_free(bat_priv, tt_global,
 361                                               "Roaming canceled");
 362                         tt_global = NULL;
 363                 } else {
 364                         /* The global entry has to be marked as ROAMING and
 365                          * has to be kept for consistency purpose
 366                          */
 367                         tt_global->common.flags |= BATADV_TT_CLIENT_ROAM;
 368                         tt_global->roam_at = jiffies;
 369                 }
 370         }
 371
 372 out:
 373         if (tt_local)
 374                 batadv_tt_local_entry_free_ref(tt_local);
 375         if (tt_global)
 376                 batadv_tt_global_entry_free_ref(tt_global);
 377 }
 378
 379 /**
 380  * batadv_tt_tvlv_container_update - update the translation table tvlv container
 381  *  after local tt changes have been committed
 382  * @bat_priv: the bat priv with all the soft interface information
 383  */
 384 static void batadv_tt_tvlv_container_update(struct batadv_priv *bat_priv)
 385 {
 386         struct batadv_tt_change_node *entry, *safe;
 387         struct batadv_tvlv_tt_data *tt_data;
 388         struct batadv_tvlv_tt_change *tt_change;
 389         int tt_diff_len = 0, tt_change_len = 0;
 390         int tt_diff_entries_num = 0, tt_diff_entries_count = 0;
 391
 392         tt_diff_len += batadv_tt_len(atomic_read(&bat_priv->tt.local_changes));
 393
 394         /* if we have too many changes for one packet don't send any
 395          * and wait for the tt table request which will be fragmented
 396          */
 397         if (tt_diff_len > bat_priv->soft_iface->mtu)
 398                 tt_diff_len = 0;
 399
 400         tt_data = kzalloc(sizeof(*tt_data) + tt_diff_len, GFP_ATOMIC);
 401         if (!tt_data)
 402                 return;
 403
 404         tt_data->flags = BATADV_TT_OGM_DIFF;
 405         tt_data->ttvn = atomic_read(&bat_priv->tt.vn);
 406         tt_data->crc = htons(bat_priv->tt.local_crc);
 407
 408         if (tt_diff_len == 0)
 409                 goto container_register;
 410
 411         tt_diff_entries_num = tt_diff_len / batadv_tt_len(1);
 412
 413         spin_lock_bh(&bat_priv->tt.changes_list_lock);
 414         atomic_set(&bat_priv->tt.local_changes, 0);
 415
 416         tt_change = (struct batadv_tvlv_tt_change *)(tt_data + 1);
 417
 418         list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
 419                                  list) {
 420                 if (tt_diff_entries_count < tt_diff_entries_num) {
 421                         memcpy(tt_change + tt_diff_entries_count,
 422                                &entry->change,
 423                                sizeof(struct batadv_tvlv_tt_change));
 424                         tt_diff_entries_count++;
 425                 }
 426                 list_del(&entry->list);
 427                 kfree(entry);
 428         }
 429         spin_unlock_bh(&bat_priv->tt.changes_list_lock);
 430
 431         /* Keep the buffer for possible tt_request */
 432         spin_lock_bh(&bat_priv->tt.last_changeset_lock);
 433         kfree(bat_priv->tt.last_changeset);
 434         bat_priv->tt.last_changeset_len = 0;
 435         bat_priv->tt.last_changeset = NULL;
 436         tt_change_len = batadv_tt_len(tt_diff_entries_count);
 437         /* check whether this new OGM has no changes due to size problems */
 438         if (tt_diff_entries_count > 0) {
 439                 /* if kmalloc() fails we will reply with the full table
 440                  * instead of providing the diff
 441                  */
 442                 bat_priv->tt.last_changeset = kzalloc(tt_diff_len, GFP_ATOMIC);
 443                 if (bat_priv->tt.last_changeset) {
 444                         memcpy(bat_priv->tt.last_changeset,
 445                                tt_change, tt_change_len);
 446                         bat_priv->tt.last_changeset_len = tt_diff_len;
 447                 }
 448         }
 449         spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
 450
 451 container_register:
 452         batadv_tvlv_container_register(bat_priv, BATADV_TVLV_TT, 1, tt_data,
 453                                        sizeof(*tt_data) + tt_change_len);
 454         kfree(tt_data);
 455 }
 456
 457 int batadv_tt_local_seq_print_text(struct seq_file *seq, void *offset)
 458 {
 459         struct net_device *net_dev = (struct net_device *)seq->private;
 460         struct batadv_priv *bat_priv = netdev_priv(net_dev);
 461         struct batadv_hashtable *hash = bat_priv->tt.local_hash;
 462         struct batadv_tt_common_entry *tt_common_entry;
 463         struct batadv_tt_local_entry *tt_local;
 464         struct batadv_hard_iface *primary_if;
 465         struct hlist_head *head;
 466         uint32_t i;
 467         int last_seen_secs;
 468         int last_seen_msecs;
 469         unsigned long last_seen_jiffies;
 470         bool no_purge;
 471         uint16_t np_flag = BATADV_TT_CLIENT_NOPURGE;
 472
 473         primary_if = batadv_seq_print_text_primary_if_get(seq);
 474         if (!primary_if)
 475                 goto out;
 476
 477         seq_printf(seq,
 478                    "Locally retrieved addresses (from %s) announced via TT (TTVN: %u CRC: %#.4x):\n",
 479                    net_dev->name, (uint8_t)atomic_read(&bat_priv->tt.vn),
 480                    bat_priv->tt.local_crc);
 481         seq_printf(seq, "       %-13s %-7s %-10s\n", "Client", "Flags",
 482                    "Last seen");
 483
 484         for (i = 0; i < hash->size; i++) {
 485                 head = &hash->table[i];
 486
 487                 rcu_read_lock();
 488                 hlist_for_each_entry_rcu(tt_common_entry,
 489                                          head, hash_entry) {
 490                         tt_local = container_of(tt_common_entry,
 491                                                 struct batadv_tt_local_entry,
 492                                                 common);
 493                         last_seen_jiffies = jiffies - tt_local->last_seen;
 494                         last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
 495                         last_seen_secs = last_seen_msecs / 1000;
 496                         last_seen_msecs = last_seen_msecs % 1000;
 497
 498                         no_purge = tt_common_entry->flags & np_flag;
 499
 500                         seq_printf(seq, " * %pM [%c%c%c%c%c] %3u.%03u\n",
 501                                    tt_common_entry->addr,
 502                                    (tt_common_entry->flags &
 503                                     BATADV_TT_CLIENT_ROAM ? 'R' : '.'),
 504                                    no_purge ? 'P' : '.',
 505                                    (tt_common_entry->flags &
 506                                     BATADV_TT_CLIENT_NEW ? 'N' : '.'),
 507                                    (tt_common_entry->flags &
 508                                     BATADV_TT_CLIENT_PENDING ? 'X' : '.'),
 509                                    (tt_common_entry->flags &
 510                                     BATADV_TT_CLIENT_WIFI ? 'W' : '.'),
 511                                    no_purge ? 0 : last_seen_secs,
 512                                    no_purge ? 0 : last_seen_msecs);
 513                 }
 514                 rcu_read_unlock();
 515         }
 516 out:
 517         if (primary_if)
 518                 batadv_hardif_free_ref(primary_if);
 519         return 0;
 520 }
 521
 522 static void
 523 batadv_tt_local_set_pending(struct batadv_priv *bat_priv,
 524                             struct batadv_tt_local_entry *tt_local_entry,
 525                             uint16_t flags, const char *message)
 526 {
 527         batadv_tt_local_event(bat_priv, tt_local_entry, flags);
 528
 529         /* The local client has to be marked as "pending to be removed" but has
 530          * to be kept in the table in order to send it in a full table
 531          * response issued before the net ttvn increment (consistency check)
 532          */
 533         tt_local_entry->common.flags |= BATADV_TT_CLIENT_PENDING;
 534
 535         batadv_dbg(BATADV_DBG_TT, bat_priv,
 536                    "Local tt entry (%pM) pending to be removed: %s\n",
 537                    tt_local_entry->common.addr, message);
 538 }
 539
 540 /**
 541  * batadv_tt_local_remove - logically remove an entry from the local table
 542  * @bat_priv: the bat priv with all the soft interface information
 543  * @addr: the MAC address of the client to remove
 544  * @message: message to append to the log on deletion
 545  * @roaming: true if the deletion is due to a roaming event
 546  *
 547  * Returns the flags assigned to the local entry before being deleted
 548  */
 549 uint16_t batadv_tt_local_remove(struct batadv_priv *bat_priv,
 550                                 const uint8_t *addr, const char *message,
 551                                 bool roaming)
 552 {
 553         struct batadv_tt_local_entry *tt_local_entry;
 554         uint16_t flags, curr_flags = BATADV_NO_FLAGS;
 555
 556         tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr);
 557         if (!tt_local_entry)
 558                 goto out;
 559
 560         curr_flags = tt_local_entry->common.flags;
 561
 562         flags = BATADV_TT_CLIENT_DEL;
 563         /* if this global entry addition is due to a roaming, the node has to
 564          * mark the local entry as "roamed" in order to correctly reroute
 565          * packets later
 566          */
 567         if (roaming) {
 568                 flags |= BATADV_TT_CLIENT_ROAM;
 569                 /* mark the local client as ROAMed */
 570                 tt_local_entry->common.flags |= BATADV_TT_CLIENT_ROAM;
 571         }
 572
 573         if (!(tt_local_entry->common.flags & BATADV_TT_CLIENT_NEW)) {
 574                 batadv_tt_local_set_pending(bat_priv, tt_local_entry, flags,
 575                                             message);
 576                 goto out;
 577         }
 578         /* if this client has been added right now, it is possible to
 579          * immediately purge it
 580          */
 581         batadv_tt_local_event(bat_priv, tt_local_entry, BATADV_TT_CLIENT_DEL);
 582         hlist_del_rcu(&tt_local_entry->common.hash_entry);
 583         batadv_tt_local_entry_free_ref(tt_local_entry);
 584
 585 out:
 586         if (tt_local_entry)
 587                 batadv_tt_local_entry_free_ref(tt_local_entry);
 588
 589         return curr_flags;
 590 }
 591
 592 static void batadv_tt_local_purge_list(struct batadv_priv *bat_priv,
 593                                        struct hlist_head *head)
 594 {
 595         struct batadv_tt_local_entry *tt_local_entry;
 596         struct batadv_tt_common_entry *tt_common_entry;
 597         struct hlist_node *node_tmp;
 598
 599         hlist_for_each_entry_safe(tt_common_entry, node_tmp, head,
 600                                   hash_entry) {
 601                 tt_local_entry = container_of(tt_common_entry,
 602                                               struct batadv_tt_local_entry,
 603                                               common);
 604                 if (tt_local_entry->common.flags & BATADV_TT_CLIENT_NOPURGE)
 605                         continue;
 606
 607                 /* entry already marked for deletion */
 608                 if (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING)
 609                         continue;
 610
 611                 if (!batadv_has_timed_out(tt_local_entry->last_seen,
 612                                           BATADV_TT_LOCAL_TIMEOUT))
 613                         continue;
 614
 615                 batadv_tt_local_set_pending(bat_priv, tt_local_entry,
 616                                             BATADV_TT_CLIENT_DEL, "timed out");
 617         }
 618 }
 619
 620 static void batadv_tt_local_purge(struct batadv_priv *bat_priv)
 621 {
 622         struct batadv_hashtable *hash = bat_priv->tt.local_hash;
 623         struct hlist_head *head;
 624         spinlock_t *list_lock; /* protects write access to the hash lists */
 625         uint32_t i;
 626
 627         for (i = 0; i < hash->size; i++) {
 628                 head = &hash->table[i];
 629                 list_lock = &hash->list_locks[i];
 630
 631                 spin_lock_bh(list_lock);
 632                 batadv_tt_local_purge_list(bat_priv, head);
 633                 spin_unlock_bh(list_lock);
 634         }
 635 }
 636
 637 static void batadv_tt_local_table_free(struct batadv_priv *bat_priv)
 638 {
 639         struct batadv_hashtable *hash;
 640         spinlock_t *list_lock; /* protects write access to the hash lists */
 641         struct batadv_tt_common_entry *tt_common_entry;
 642         struct batadv_tt_local_entry *tt_local;
 643         struct hlist_node *node_tmp;
 644         struct hlist_head *head;
 645         uint32_t i;
 646
 647         if (!bat_priv->tt.local_hash)
 648                 return;
 649
 650         hash = bat_priv->tt.local_hash;
 651
 652         for (i = 0; i < hash->size; i++) {
 653                 head = &hash->table[i];
 654                 list_lock = &hash->list_locks[i];
 655
 656                 spin_lock_bh(list_lock);
 657                 hlist_for_each_entry_safe(tt_common_entry, node_tmp,
 658                                           head, hash_entry) {
 659                         hlist_del_rcu(&tt_common_entry->hash_entry);
 660                         tt_local = container_of(tt_common_entry,
 661                                                 struct batadv_tt_local_entry,
 662                                                 common);
 663                         batadv_tt_local_entry_free_ref(tt_local);
 664                 }
 665                 spin_unlock_bh(list_lock);
 666         }
 667
 668         batadv_hash_destroy(hash);
 669
 670         bat_priv->tt.local_hash = NULL;
 671 }
 672
 673 static int batadv_tt_global_init(struct batadv_priv *bat_priv)
 674 {
 675         if (bat_priv->tt.global_hash)
 676                 return 0;
 677
 678         bat_priv->tt.global_hash = batadv_hash_new(1024);
 679
 680         if (!bat_priv->tt.global_hash)
 681                 return -ENOMEM;
 682
 683         batadv_hash_set_lock_class(bat_priv->tt.global_hash,
 684                                    &batadv_tt_global_hash_lock_class_key);
 685
 686         return 0;
 687 }
 688
 689 static void batadv_tt_changes_list_free(struct batadv_priv *bat_priv)
 690 {
 691         struct batadv_tt_change_node *entry, *safe;
 692
 693         spin_lock_bh(&bat_priv->tt.changes_list_lock);
 694
 695         list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
 696                                  list) {
 697                 list_del(&entry->list);
 698                 kfree(entry);
 699         }
 700
 701         atomic_set(&bat_priv->tt.local_changes, 0);
 702         spin_unlock_bh(&bat_priv->tt.changes_list_lock);
 703 }
 704
 705 /* retrieves the orig_tt_list_entry belonging to orig_node from the
 706  * batadv_tt_global_entry list
 707  *
 708  * returns it with an increased refcounter, NULL if not found
 709  */
 710 static struct batadv_tt_orig_list_entry *
 711 batadv_tt_global_orig_entry_find(const struct batadv_tt_global_entry *entry,
 712                                  const struct batadv_orig_node *orig_node)
 713 {
 714         struct batadv_tt_orig_list_entry *tmp_orig_entry, *orig_entry = NULL;
 715         const struct hlist_head *head;
 716
 717         rcu_read_lock();
 718         head = &entry->orig_list;
 719         hlist_for_each_entry_rcu(tmp_orig_entry, head, list) {
 720                 if (tmp_orig_entry->orig_node != orig_node)
 721                         continue;
 722                 if (!atomic_inc_not_zero(&tmp_orig_entry->refcount))
 723                         continue;
 724
 725                 orig_entry = tmp_orig_entry;
 726                 break;
 727         }
 728         rcu_read_unlock();
 729
 730         return orig_entry;
 731 }
 732
 733 /* find out if an orig_node is already in the list of a tt_global_entry.
 734  * returns true if found, false otherwise
 735  */
 736 static bool
 737 batadv_tt_global_entry_has_orig(const struct batadv_tt_global_entry *entry,
 738                                 const struct batadv_orig_node *orig_node)
 739 {
 740         struct batadv_tt_orig_list_entry *orig_entry;
 741         bool found = false;
 742
 743         orig_entry = batadv_tt_global_orig_entry_find(entry, orig_node);
 744         if (orig_entry) {
 745                 found = true;
 746                 batadv_tt_orig_list_entry_free_ref(orig_entry);
 747         }
 748
 749         return found;
 750 }
 751
 752 static void
 753 batadv_tt_global_orig_entry_add(struct batadv_tt_global_entry *tt_global,
 754                                 struct batadv_orig_node *orig_node, int ttvn)
 755 {
 756         struct batadv_tt_orig_list_entry *orig_entry;
 757
 758         orig_entry = batadv_tt_global_orig_entry_find(tt_global, orig_node);
 759         if (orig_entry) {
 760                 /* refresh the ttvn: the current value could be a bogus one that
 761                  * was added during a "temporary client detection"
 762                  */
 763                 orig_entry->ttvn = ttvn;
 764                 goto out;
 765         }
 766
 767         orig_entry = kzalloc(sizeof(*orig_entry), GFP_ATOMIC);
 768         if (!orig_entry)
 769                 goto out;
 770
 771         INIT_HLIST_NODE(&orig_entry->list);
 772         atomic_inc(&orig_node->refcount);
 773         atomic_inc(&orig_node->tt_size);
 774         orig_entry->orig_node = orig_node;
 775         orig_entry->ttvn = ttvn;
 776         atomic_set(&orig_entry->refcount, 2);
 777
 778         spin_lock_bh(&tt_global->list_lock);
 779         hlist_add_head_rcu(&orig_entry->list,
 780                            &tt_global->orig_list);
 781         spin_unlock_bh(&tt_global->list_lock);
 782 out:
 783         if (orig_entry)
 784                 batadv_tt_orig_list_entry_free_ref(orig_entry);
 785 }
 786
 787 /**
 788  * batadv_tt_global_add - add a new TT global entry or update an existing one
 789  * @bat_priv: the bat priv with all the soft interface information
 790  * @orig_node: the originator announcing the client
 791  * @tt_addr: the mac address of the non-mesh client
 792  * @flags: TT flags that have to be set for this non-mesh client
 793  * @ttvn: the tt version number ever announcing this non-mesh client
 794  *
 795  * Add a new TT global entry for the given originator. If the entry already
 796  * exists add a new reference to the given originator (a global entry can have
 797  * references to multiple originators) and adjust the flags attribute to reflect
 798  * the function argument.
 799  * If a TT local entry exists for this non-mesh client remove it.
 800  *
 801  * The caller must hold orig_node refcount.
 802  */
 803 int batadv_tt_global_add(struct batadv_priv *bat_priv,
 804                          struct batadv_orig_node *orig_node,
 805                          const unsigned char *tt_addr, uint16_t flags,
 806                          uint8_t ttvn)
 807 {
 808         struct batadv_tt_global_entry *tt_global_entry;
 809         struct batadv_tt_local_entry *tt_local_entry;
 810         int ret = 0;
 811         int hash_added;
 812         struct batadv_tt_common_entry *common;
 813         uint16_t local_flags;
 814
 815         tt_global_entry = batadv_tt_global_hash_find(bat_priv, tt_addr);
 816         tt_local_entry = batadv_tt_local_hash_find(bat_priv, tt_addr);
 817
 818         /* if the node already has a local client for this entry, it has to wait
 819          * for a roaming advertisement instead of manually messing up the global
 820          * table
 821          */
 822         if ((flags & BATADV_TT_CLIENT_TEMP) && tt_local_entry &&
 823             !(tt_local_entry->common.flags & BATADV_TT_CLIENT_NEW))
 824                 goto out;
 825
 826         if (!tt_global_entry) {
 827                 tt_global_entry = kzalloc(sizeof(*tt_global_entry), GFP_ATOMIC);
 828                 if (!tt_global_entry)
 829                         goto out;
 830
 831                 common = &tt_global_entry->common;
 832                 memcpy(common->addr, tt_addr, ETH_ALEN);
 833
 834                 common->flags = flags;
 835                 tt_global_entry->roam_at = 0;
 836                 /* node must store current time in case of roaming. This is
 837                  * needed to purge this entry out on timeout (if nobody claims
 838                  * it)
 839                  */
 840                 if (flags & BATADV_TT_CLIENT_ROAM)
 841                         tt_global_entry->roam_at = jiffies;
 842                 atomic_set(&common->refcount, 2);
 843                 common->added_at = jiffies;
 844
 845                 INIT_HLIST_HEAD(&tt_global_entry->orig_list);
 846                 spin_lock_init(&tt_global_entry->list_lock);
 847
 848                 hash_added = batadv_hash_add(bat_priv->tt.global_hash,
 849                                              batadv_compare_tt,
 850                                              batadv_choose_orig, common,
 851                                              &common->hash_entry);
 852
 853                 if (unlikely(hash_added != 0)) {
 854                         /* remove the reference for the hash */
 855                         batadv_tt_global_entry_free_ref(tt_global_entry);
 856                         goto out_remove;
 857                 }
 858         } else {
 859                 common = &tt_global_entry->common;
 860                 /* If there is already a global entry, we can use this one for
 861                  * our processing.
 862                  * But if we are trying to add a temporary client then here are
 863                  * two options at this point:
 864                  * 1) the global client is not a temporary client: the global
 865                  *    client has to be left as it is, temporary information
 866                  *    should never override any already known client state
 867                  * 2) the global client is a temporary client: purge the
 868                  *    originator list and add the new one orig_entry
 869                  */
 870                 if (flags & BATADV_TT_CLIENT_TEMP) {
 871                         if (!(common->flags & BATADV_TT_CLIENT_TEMP))
 872                                 goto out;
 873                         if (batadv_tt_global_entry_has_orig(tt_global_entry,
 874                                                             orig_node))
 875                                 goto out_remove;
 876                         batadv_tt_global_del_orig_list(tt_global_entry);
 877                         goto add_orig_entry;
 878                 }
 879
 880                 /* if the client was temporary added before receiving the first
 881                  * OGM announcing it, we have to clear the TEMP flag
 882                  */
 883                 common->flags &= ~BATADV_TT_CLIENT_TEMP;
 884
 885                 /* the change can carry possible "attribute" flags like the
 886                  * TT_CLIENT_WIFI, therefore they have to be copied in the
 887                  * client entry
 888                  */
 889                 tt_global_entry->common.flags |= flags;
 890
 891                 /* If there is the BATADV_TT_CLIENT_ROAM flag set, there is only
 892                  * one originator left in the list and we previously received a
 893                  * delete + roaming change for this originator.
 894                  *
 895                  * We should first delete the old originator before adding the
 896                  * new one.
 897                  */
 898                 if (common->flags & BATADV_TT_CLIENT_ROAM) {
 899                         batadv_tt_global_del_orig_list(tt_global_entry);
 900                         common->flags &= ~BATADV_TT_CLIENT_ROAM;
 901                         tt_global_entry->roam_at = 0;
 902                 }
 903         }
 904 add_orig_entry:
 905         /* add the new orig_entry (if needed) or update it */
 906         batadv_tt_global_orig_entry_add(tt_global_entry, orig_node, ttvn);
 907
 908         batadv_dbg(BATADV_DBG_TT, bat_priv,
 909                    "Creating new global tt entry: %pM (via %pM)\n",
 910                    common->addr, orig_node->orig);
 911         ret = 1;
 912
 913 out_remove:
 914
 915         /* remove address from local hash if present */
 916         local_flags = batadv_tt_local_remove(bat_priv, tt_addr,
 917                                              "global tt received",
 918                                              flags & BATADV_TT_CLIENT_ROAM);
 919         tt_global_entry->common.flags |= local_flags & BATADV_TT_CLIENT_WIFI;
 920
 921         if (!(flags & BATADV_TT_CLIENT_ROAM))
 922                 /* this is a normal global add. Therefore the client is not in a
 923                  * roaming state anymore.
 924                  */
 925                 tt_global_entry->common.flags &= ~BATADV_TT_CLIENT_ROAM;
 926
 927 out:
 928         if (tt_global_entry)
 929                 batadv_tt_global_entry_free_ref(tt_global_entry);
 930         if (tt_local_entry)
 931                 batadv_tt_local_entry_free_ref(tt_local_entry);
 932         return ret;
 933 }
 934
 935 /* batadv_transtable_best_orig - Get best originator list entry from tt entry
 936  * @tt_global_entry: global translation table entry to be analyzed
 937  *
 938  * This functon assumes the caller holds rcu_read_lock().
 939  * Returns best originator list entry or NULL on errors.
 940  */
 941 static struct batadv_tt_orig_list_entry *
 942 batadv_transtable_best_orig(struct batadv_tt_global_entry *tt_global_entry)
 943 {
 944         struct batadv_neigh_node *router = NULL;
 945         struct hlist_head *head;
 946         struct batadv_tt_orig_list_entry *orig_entry, *best_entry = NULL;
 947         int best_tq = 0;
 948
 949         head = &tt_global_entry->orig_list;
 950         hlist_for_each_entry_rcu(orig_entry, head, list) {
 951                 router = batadv_orig_node_get_router(orig_entry->orig_node);
 952                 if (!router)
 953                         continue;
 954
 955                 if (router->tq_avg > best_tq) {
 956                         best_entry = orig_entry;
 957                         best_tq = router->tq_avg;
 958                 }
 959
 960                 batadv_neigh_node_free_ref(router);
 961         }
 962
 963         return best_entry;
 964 }
 965
 966 /* batadv_tt_global_print_entry - print all orig nodes who announce the address
 967  * for this global entry
 968  * @tt_global_entry: global translation table entry to be printed
 969  * @seq: debugfs table seq_file struct
 970  *
 971  * This functon assumes the caller holds rcu_read_lock().
 972  */
 973 static void
 974 batadv_tt_global_print_entry(struct batadv_tt_global_entry *tt_global_entry,
 975                              struct seq_file *seq)
 976 {
 977         struct hlist_head *head;
 978         struct batadv_tt_orig_list_entry *orig_entry, *best_entry;
 979         struct batadv_tt_common_entry *tt_common_entry;
 980         uint16_t flags;
 981         uint8_t last_ttvn;
 982
 983         tt_common_entry = &tt_global_entry->common;
 984         flags = tt_common_entry->flags;
 985
 986         best_entry = batadv_transtable_best_orig(tt_global_entry);
 987         if (best_entry) {
 988                 last_ttvn = atomic_read(&best_entry->orig_node->last_ttvn);
 989                 seq_printf(seq,
 990                            " %c %pM  (%3u) via %pM     (%3u)   (%#.4x) [%c%c%c]\n",
 991                            '*', tt_global_entry->common.addr,
 992                            best_entry->ttvn, best_entry->orig_node->orig,
 993                            last_ttvn, best_entry->orig_node->tt_crc,
 994                            (flags & BATADV_TT_CLIENT_ROAM ? 'R' : '.'),
 995                            (flags & BATADV_TT_CLIENT_WIFI ? 'W' : '.'),
 996                            (flags & BATADV_TT_CLIENT_TEMP ? 'T' : '.'));
 997         }
 998
 999         head = &tt_global_entry->orig_list;
1000
1001         hlist_for_each_entry_rcu(orig_entry, head, list) {
1002                 if (best_entry == orig_entry)
1003                         continue;
1004
1005                 last_ttvn = atomic_read(&orig_entry->orig_node->last_ttvn);
1006                 seq_printf(seq, " %c %pM  (%3u) via %pM     (%3u)   [%c%c%c]\n",
1007                            '+', tt_global_entry->common.addr,
1008                            orig_entry->ttvn, orig_entry->orig_node->orig,
1009                            last_ttvn,
1010                            (flags & BATADV_TT_CLIENT_ROAM ? 'R' : '.'),
1011                            (flags & BATADV_TT_CLIENT_WIFI ? 'W' : '.'),
1012                            (flags & BATADV_TT_CLIENT_TEMP ? 'T' : '.'));
1013         }
1014 }
1015
1016 int batadv_tt_global_seq_print_text(struct seq_file *seq, void *offset)
1017 {
1018         struct net_device *net_dev = (struct net_device *)seq->private;
1019         struct batadv_priv *bat_priv = netdev_priv(net_dev);
1020         struct batadv_hashtable *hash = bat_priv->tt.global_hash;
1021         struct batadv_tt_common_entry *tt_common_entry;
1022         struct batadv_tt_global_entry *tt_global;
1023         struct batadv_hard_iface *primary_if;
1024         struct hlist_head *head;
1025         uint32_t i;
1026
1027         primary_if = batadv_seq_print_text_primary_if_get(seq);
1028         if (!primary_if)
1029                 goto out;
1030
1031         seq_printf(seq,
1032                    "Globally announced TT entries received via the mesh %s\n",
1033                    net_dev->name);
1034         seq_printf(seq, "       %-13s %s       %-15s %s (%-6s) %s\n",
1035                    "Client", "(TTVN)", "Originator", "(Curr TTVN)", "CRC",
1036                    "Flags");
1037
1038         for (i = 0; i < hash->size; i++) {
1039                 head = &hash->table[i];
1040
1041                 rcu_read_lock();
1042                 hlist_for_each_entry_rcu(tt_common_entry,
1043                                          head, hash_entry) {
1044                         tt_global = container_of(tt_common_entry,
1045                                                  struct batadv_tt_global_entry,
1046                                                  common);
1047                         batadv_tt_global_print_entry(tt_global, seq);
1048                 }
1049                 rcu_read_unlock();
1050         }
1051 out:
1052         if (primary_if)
1053                 batadv_hardif_free_ref(primary_if);
1054         return 0;
1055 }
1056
1057 /* deletes the orig list of a tt_global_entry */
1058 static void
1059 batadv_tt_global_del_orig_list(struct batadv_tt_global_entry *tt_global_entry)
1060 {
1061         struct hlist_head *head;
1062         struct hlist_node *safe;
1063         struct batadv_tt_orig_list_entry *orig_entry;
1064
1065         spin_lock_bh(&tt_global_entry->list_lock);
1066         head = &tt_global_entry->orig_list;
1067         hlist_for_each_entry_safe(orig_entry, safe, head, list) {
1068                 hlist_del_rcu(&orig_entry->list);
1069                 batadv_tt_orig_list_entry_free_ref(orig_entry);
1070         }
1071         spin_unlock_bh(&tt_global_entry->list_lock);
1072 }
1073
1074 static void
1075 batadv_tt_global_del_orig_entry(struct batadv_priv *bat_priv,
1076                                 struct batadv_tt_global_entry *tt_global_entry,
1077                                 struct batadv_orig_node *orig_node,
1078                                 const char *message)
1079 {
1080         struct hlist_head *head;
1081         struct hlist_node *safe;
1082         struct batadv_tt_orig_list_entry *orig_entry;
1083
1084         spin_lock_bh(&tt_global_entry->list_lock);
1085         head = &tt_global_entry->orig_list;
1086         hlist_for_each_entry_safe(orig_entry, safe, head, list) {
1087                 if (orig_entry->orig_node == orig_node) {
1088                         batadv_dbg(BATADV_DBG_TT, bat_priv,
1089                                    "Deleting %pM from global tt entry %pM: %s\n",
1090                                    orig_node->orig,
1091                                    tt_global_entry->common.addr, message);
1092                         hlist_del_rcu(&orig_entry->list);
1093                         batadv_tt_orig_list_entry_free_ref(orig_entry);
1094                 }
1095         }
1096         spin_unlock_bh(&tt_global_entry->list_lock);
1097 }
1098
1099 /* If the client is to be deleted, we check if it is the last origantor entry
1100  * within tt_global entry. If yes, we set the BATADV_TT_CLIENT_ROAM flag and the
1101  * timer, otherwise we simply remove the originator scheduled for deletion.
1102  */
1103 static void
1104 batadv_tt_global_del_roaming(struct batadv_priv *bat_priv,
1105                              struct batadv_tt_global_entry *tt_global_entry,
1106                              struct batadv_orig_node *orig_node,
1107                              const char *message)
1108 {
1109         bool last_entry = true;
1110         struct hlist_head *head;
1111         struct batadv_tt_orig_list_entry *orig_entry;
1112
1113         /* no local entry exists, case 1:
1114          * Check if this is the last one or if other entries exist.
1115          */
1116
1117         rcu_read_lock();
1118         head = &tt_global_entry->orig_list;
1119         hlist_for_each_entry_rcu(orig_entry, head, list) {
1120                 if (orig_entry->orig_node != orig_node) {
1121                         last_entry = false;
1122                         break;
1123                 }
1124         }
1125         rcu_read_unlock();
1126
1127         if (last_entry) {
1128                 /* its the last one, mark for roaming. */
1129                 tt_global_entry->common.flags |= BATADV_TT_CLIENT_ROAM;
1130                 tt_global_entry->roam_at = jiffies;
1131         } else
1132                 /* there is another entry, we can simply delete this
1133                  * one and can still use the other one.
1134                  */
1135                 batadv_tt_global_del_orig_entry(bat_priv, tt_global_entry,
1136                                                 orig_node, message);
1137 }
1138
1139
1140
1141 static void batadv_tt_global_del(struct batadv_priv *bat_priv,
1142                                  struct batadv_orig_node *orig_node,
1143                                  const unsigned char *addr,
1144                                  const char *message, bool roaming)
1145 {
1146         struct batadv_tt_global_entry *tt_global_entry;
1147         struct batadv_tt_local_entry *local_entry = NULL;
1148
1149         tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr);
1150         if (!tt_global_entry)
1151                 goto out;
1152
1153         if (!roaming) {
1154                 batadv_tt_global_del_orig_entry(bat_priv, tt_global_entry,
1155                                                 orig_node, message);
1156
1157                 if (hlist_empty(&tt_global_entry->orig_list))
1158                         batadv_tt_global_free(bat_priv, tt_global_entry,
1159                                               message);
1160
1161                 goto out;
1162         }
1163
1164         /* if we are deleting a global entry due to a roam
1165          * event, there are two possibilities:
1166          * 1) the client roamed from node A to node B => if there
1167          *    is only one originator left for this client, we mark
1168          *    it with BATADV_TT_CLIENT_ROAM, we start a timer and we
1169          *    wait for node B to claim it. In case of timeout
1170          *    the entry is purged.
1171          *
1172          *    If there are other originators left, we directly delete
1173          *    the originator.
1174          * 2) the client roamed to us => we can directly delete
1175          *    the global entry, since it is useless now.
1176          */
1177         local_entry = batadv_tt_local_hash_find(bat_priv,
1178                                                 tt_global_entry->common.addr);
1179         if (local_entry) {
1180                 /* local entry exists, case 2: client roamed to us. */
1181                 batadv_tt_global_del_orig_list(tt_global_entry);
1182                 batadv_tt_global_free(bat_priv, tt_global_entry, message);
1183         } else
1184                 /* no local entry exists, case 1: check for roaming */
1185                 batadv_tt_global_del_roaming(bat_priv, tt_global_entry,
1186                                              orig_node, message);
1187
1188
1189 out:
1190         if (tt_global_entry)
1191                 batadv_tt_global_entry_free_ref(tt_global_entry);
1192         if (local_entry)
1193                 batadv_tt_local_entry_free_ref(local_entry);
1194 }
1195
1196 void batadv_tt_global_del_orig(struct batadv_priv *bat_priv,
1197                                struct batadv_orig_node *orig_node,
1198                                const char *message)
1199 {
1200         struct batadv_tt_global_entry *tt_global;
1201         struct batadv_tt_common_entry *tt_common_entry;
1202         uint32_t i;
1203         struct batadv_hashtable *hash = bat_priv->tt.global_hash;
1204         struct hlist_node *safe;
1205         struct hlist_head *head;
1206         spinlock_t *list_lock; /* protects write access to the hash lists */
1207
1208         if (!hash)
1209                 return;
1210
1211         for (i = 0; i < hash->size; i++) {
1212                 head = &hash->table[i];
1213                 list_lock = &hash->list_locks[i];
1214
1215                 spin_lock_bh(list_lock);
1216                 hlist_for_each_entry_safe(tt_common_entry, safe,
1217                                           head, hash_entry) {
1218                         tt_global = container_of(tt_common_entry,
1219                                                  struct batadv_tt_global_entry,
1220                                                  common);
1221
1222                         batadv_tt_global_del_orig_entry(bat_priv, tt_global,
1223                                                         orig_node, message);
1224
1225                         if (hlist_empty(&tt_global->orig_list)) {
1226                                 batadv_dbg(BATADV_DBG_TT, bat_priv,
1227                                            "Deleting global tt entry %pM: %s\n",
1228                                            tt_global->common.addr, message);
1229                                 hlist_del_rcu(&tt_common_entry->hash_entry);
1230                                 batadv_tt_global_entry_free_ref(tt_global);
1231                         }
1232                 }
1233                 spin_unlock_bh(list_lock);
1234         }
1235         orig_node->tt_initialised = false;
1236 }
1237
1238 static bool batadv_tt_global_to_purge(struct batadv_tt_global_entry *tt_global,
1239                                       char **msg)
1240 {
1241         bool purge = false;
1242         unsigned long roam_timeout = BATADV_TT_CLIENT_ROAM_TIMEOUT;
1243         unsigned long temp_timeout = BATADV_TT_CLIENT_TEMP_TIMEOUT;
1244
1245         if ((tt_global->common.flags & BATADV_TT_CLIENT_ROAM) &&
1246             batadv_has_timed_out(tt_global->roam_at, roam_timeout)) {
1247                 purge = true;
1248                 *msg = "Roaming timeout\n";
1249         }
1250
1251         if ((tt_global->common.flags & BATADV_TT_CLIENT_TEMP) &&
1252             batadv_has_timed_out(tt_global->common.added_at, temp_timeout)) {
1253                 purge = true;
1254                 *msg = "Temporary client timeout\n";
1255         }
1256
1257         return purge;
1258 }
1259
1260 static void batadv_tt_global_purge(struct batadv_priv *bat_priv)
1261 {
1262         struct batadv_hashtable *hash = bat_priv->tt.global_hash;
1263         struct hlist_head *head;
1264         struct hlist_node *node_tmp;
1265         spinlock_t *list_lock; /* protects write access to the hash lists */
1266         uint32_t i;
1267         char *msg = NULL;
1268         struct batadv_tt_common_entry *tt_common;
1269         struct batadv_tt_global_entry *tt_global;
1270
1271         for (i = 0; i < hash->size; i++) {
1272                 head = &hash->table[i];
1273                 list_lock = &hash->list_locks[i];
1274
1275                 spin_lock_bh(list_lock);
1276                 hlist_for_each_entry_safe(tt_common, node_tmp, head,
1277                                           hash_entry) {
1278                         tt_global = container_of(tt_common,
1279                                                  struct batadv_tt_global_entry,
1280                                                  common);
1281
1282                         if (!batadv_tt_global_to_purge(tt_global, &msg))
1283                                 continue;
1284
1285                         batadv_dbg(BATADV_DBG_TT, bat_priv,
1286                                    "Deleting global tt entry (%pM): %s\n",
1287                                    tt_global->common.addr, msg);
1288
1289                         hlist_del_rcu(&tt_common->hash_entry);
1290
1291                         batadv_tt_global_entry_free_ref(tt_global);
1292                 }
1293                 spin_unlock_bh(list_lock);
1294         }
1295 }
1296
1297 static void batadv_tt_global_table_free(struct batadv_priv *bat_priv)
1298 {
1299         struct batadv_hashtable *hash;
1300         spinlock_t *list_lock; /* protects write access to the hash lists */
1301         struct batadv_tt_common_entry *tt_common_entry;
1302         struct batadv_tt_global_entry *tt_global;
1303         struct hlist_node *node_tmp;
1304         struct hlist_head *head;
1305         uint32_t i;
1306
1307         if (!bat_priv->tt.global_hash)
1308                 return;
1309
1310         hash = bat_priv->tt.global_hash;
1311
1312         for (i = 0; i < hash->size; i++) {
1313                 head = &hash->table[i];
1314                 list_lock = &hash->list_locks[i];
1315
1316                 spin_lock_bh(list_lock);
1317                 hlist_for_each_entry_safe(tt_common_entry, node_tmp,
1318                                           head, hash_entry) {
1319                         hlist_del_rcu(&tt_common_entry->hash_entry);
1320                         tt_global = container_of(tt_common_entry,
1321                                                  struct batadv_tt_global_entry,
1322                                                  common);
1323                         batadv_tt_global_entry_free_ref(tt_global);
1324                 }
1325                 spin_unlock_bh(list_lock);
1326         }
1327
1328         batadv_hash_destroy(hash);
1329
1330         bat_priv->tt.global_hash = NULL;
1331 }
1332
1333 static bool
1334 _batadv_is_ap_isolated(struct batadv_tt_local_entry *tt_local_entry,
1335                        struct batadv_tt_global_entry *tt_global_entry)
1336 {
1337         bool ret = false;
1338
1339         if (tt_local_entry->common.flags & BATADV_TT_CLIENT_WIFI &&
1340             tt_global_entry->common.flags & BATADV_TT_CLIENT_WIFI)
1341                 ret = true;
1342
1343         return ret;
1344 }
1345
1346 struct batadv_orig_node *batadv_transtable_search(struct batadv_priv *bat_priv,
1347                                                   const uint8_t *src,
1348                                                   const uint8_t *addr)
1349 {
1350         struct batadv_tt_local_entry *tt_local_entry = NULL;
1351         struct batadv_tt_global_entry *tt_global_entry = NULL;
1352         struct batadv_orig_node *orig_node = NULL;
1353         struct batadv_tt_orig_list_entry *best_entry;
1354
1355         if (src && atomic_read(&bat_priv->ap_isolation)) {
1356                 tt_local_entry = batadv_tt_local_hash_find(bat_priv, src);
1357                 if (!tt_local_entry ||
1358                     (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING))
1359                         goto out;
1360         }
1361
1362         tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr);
1363         if (!tt_global_entry)
1364                 goto out;
1365
1366         /* check whether the clients should not communicate due to AP
1367          * isolation
1368          */
1369         if (tt_local_entry &&
1370             _batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
1371                 goto out;
1372
1373         rcu_read_lock();
1374         best_entry = batadv_transtable_best_orig(tt_global_entry);
1375         /* found anything? */
1376         if (best_entry)
1377                 orig_node = best_entry->orig_node;
1378         if (orig_node && !atomic_inc_not_zero(&orig_node->refcount))
1379                 orig_node = NULL;
1380         rcu_read_unlock();
1381
1382 out:
1383         if (tt_global_entry)
1384                 batadv_tt_global_entry_free_ref(tt_global_entry);
1385         if (tt_local_entry)
1386                 batadv_tt_local_entry_free_ref(tt_local_entry);
1387
1388         return orig_node;
1389 }
1390
1391 /* Calculates the checksum of the local table of a given orig_node */
1392 static uint16_t batadv_tt_global_crc(struct batadv_priv *bat_priv,
1393                                      struct batadv_orig_node *orig_node)
1394 {
1395         uint16_t total = 0, total_one;
1396         struct batadv_hashtable *hash = bat_priv->tt.global_hash;
1397         struct batadv_tt_common_entry *tt_common;
1398         struct batadv_tt_global_entry *tt_global;
1399         struct hlist_head *head;
1400         uint32_t i;
1401         int j;
1402
1403         for (i = 0; i < hash->size; i++) {
1404                 head = &hash->table[i];
1405
1406                 rcu_read_lock();
1407                 hlist_for_each_entry_rcu(tt_common, head, hash_entry) {
1408                         tt_global = container_of(tt_common,
1409                                                  struct batadv_tt_global_entry,
1410                                                  common);
1411                         /* Roaming clients are in the global table for
1412                          * consistency only. They don't have to be
1413                          * taken into account while computing the
1414                          * global crc
1415                          */
1416                         if (tt_common->flags & BATADV_TT_CLIENT_ROAM)
1417                                 continue;
1418                         /* Temporary clients have not been announced yet, so
1419                          * they have to be skipped while computing the global
1420                          * crc
1421                          */
1422                         if (tt_common->flags & BATADV_TT_CLIENT_TEMP)
1423                                 continue;
1424
1425                         /* find out if this global entry is announced by this
1426                          * originator
1427                          */
1428                         if (!batadv_tt_global_entry_has_orig(tt_global,
1429                                                              orig_node))
1430                                 continue;
1431
1432                         total_one = 0;
1433                         for (j = 0; j < ETH_ALEN; j++)
1434                                 total_one = crc16_byte(total_one,
1435                                                        tt_common->addr[j]);
1436                         total ^= total_one;
1437                 }
1438                 rcu_read_unlock();
1439         }
1440
1441         return total;
1442 }
1443
1444 /* Calculates the checksum of the local table */
1445 static uint16_t batadv_tt_local_crc(struct batadv_priv *bat_priv)
1446 {
1447         uint16_t total = 0, total_one;
1448         struct batadv_hashtable *hash = bat_priv->tt.local_hash;
1449         struct batadv_tt_common_entry *tt_common;
1450         struct hlist_head *head;
1451         uint32_t i;
1452         int j;
1453
1454         for (i = 0; i < hash->size; i++) {
1455                 head = &hash->table[i];
1456
1457                 rcu_read_lock();
1458                 hlist_for_each_entry_rcu(tt_common, head, hash_entry) {
1459                         /* not yet committed clients have not to be taken into
1460                          * account while computing the CRC
1461                          */
1462                         if (tt_common->flags & BATADV_TT_CLIENT_NEW)
1463                                 continue;
1464                         total_one = 0;
1465                         for (j = 0; j < ETH_ALEN; j++)
1466                                 total_one = crc16_byte(total_one,
1467                                                        tt_common->addr[j]);
1468                         total ^= total_one;
1469                 }
1470                 rcu_read_unlock();
1471         }
1472
1473         return total;
1474 }
1475
1476 static void batadv_tt_req_list_free(struct batadv_priv *bat_priv)
1477 {
1478         struct batadv_tt_req_node *node, *safe;
1479
1480         spin_lock_bh(&bat_priv->tt.req_list_lock);
1481
1482         list_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
1483                 list_del(&node->list);
1484                 kfree(node);
1485         }
1486
1487         spin_unlock_bh(&bat_priv->tt.req_list_lock);
1488 }
1489
1490 static void batadv_tt_save_orig_buffer(struct batadv_priv *bat_priv,
1491                                        struct batadv_orig_node *orig_node,
1492                                        const unsigned char *tt_buff,
1493                                        uint16_t tt_num_changes)
1494 {
1495         uint16_t tt_buff_len = batadv_tt_len(tt_num_changes);
1496
1497         /* Replace the old buffer only if I received something in the
1498          * last OGM (the OGM could carry no changes)
1499          */
1500         spin_lock_bh(&orig_node->tt_buff_lock);
1501         if (tt_buff_len > 0) {
1502                 kfree(orig_node->tt_buff);
1503                 orig_node->tt_buff_len = 0;
1504                 orig_node->tt_buff = kmalloc(tt_buff_len, GFP_ATOMIC);
1505                 if (orig_node->tt_buff) {
1506                         memcpy(orig_node->tt_buff, tt_buff, tt_buff_len);
1507                         orig_node->tt_buff_len = tt_buff_len;
1508                 }
1509         }
1510         spin_unlock_bh(&orig_node->tt_buff_lock);
1511 }
1512
1513 static void batadv_tt_req_purge(struct batadv_priv *bat_priv)
1514 {
1515         struct batadv_tt_req_node *node, *safe;
1516
1517         spin_lock_bh(&bat_priv->tt.req_list_lock);
1518         list_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
1519                 if (batadv_has_timed_out(node->issued_at,
1520                                          BATADV_TT_REQUEST_TIMEOUT)) {
1521                         list_del(&node->list);
1522                         kfree(node);
1523                 }
1524         }
1525         spin_unlock_bh(&bat_priv->tt.req_list_lock);
1526 }
1527
1528 /* returns the pointer to the new tt_req_node struct if no request
1529  * has already been issued for this orig_node, NULL otherwise
1530  */
1531 static struct batadv_tt_req_node *
1532 batadv_new_tt_req_node(struct batadv_priv *bat_priv,
1533                        struct batadv_orig_node *orig_node)
1534 {
1535         struct batadv_tt_req_node *tt_req_node_tmp, *tt_req_node = NULL;
1536
1537         spin_lock_bh(&bat_priv->tt.req_list_lock);
1538         list_for_each_entry(tt_req_node_tmp, &bat_priv->tt.req_list, list) {
1539                 if (batadv_compare_eth(tt_req_node_tmp, orig_node) &&
1540                     !batadv_has_timed_out(tt_req_node_tmp->issued_at,
1541                                           BATADV_TT_REQUEST_TIMEOUT))
1542                         goto unlock;
1543         }
1544
1545         tt_req_node = kmalloc(sizeof(*tt_req_node), GFP_ATOMIC);
1546         if (!tt_req_node)
1547                 goto unlock;
1548
1549         memcpy(tt_req_node->addr, orig_node->orig, ETH_ALEN);
1550         tt_req_node->issued_at = jiffies;
1551
1552         list_add(&tt_req_node->list, &bat_priv->tt.req_list);
1553 unlock:
1554         spin_unlock_bh(&bat_priv->tt.req_list_lock);
1555         return tt_req_node;
1556 }
1557
1558 /* data_ptr is useless here, but has to be kept to respect the prototype */
1559 static int batadv_tt_local_valid_entry(const void *entry_ptr,
1560                                        const void *data_ptr)
1561 {
1562         const struct batadv_tt_common_entry *tt_common_entry = entry_ptr;
1563
1564         if (tt_common_entry->flags & BATADV_TT_CLIENT_NEW)
1565                 return 0;
1566         return 1;
1567 }
1568
1569 static int batadv_tt_global_valid(const void *entry_ptr,
1570                                   const void *data_ptr)
1571 {
1572         const struct batadv_tt_common_entry *tt_common_entry = entry_ptr;
1573         const struct batadv_tt_global_entry *tt_global_entry;
1574         const struct batadv_orig_node *orig_node = data_ptr;
1575
1576         if (tt_common_entry->flags & BATADV_TT_CLIENT_ROAM ||
1577             tt_common_entry->flags & BATADV_TT_CLIENT_TEMP)
1578                 return 0;
1579
1580         tt_global_entry = container_of(tt_common_entry,
1581                                        struct batadv_tt_global_entry,
1582                                        common);
1583
1584         return batadv_tt_global_entry_has_orig(tt_global_entry, orig_node);
1585 }
1586
1587 static struct sk_buff *
1588 batadv_tt_response_fill_table(uint16_t tt_len, uint8_t ttvn,
1589                               struct batadv_hashtable *hash,
1590                               struct batadv_priv *bat_priv,
1591                               int (*valid_cb)(const void *, const void *),
1592                               void *cb_data)
1593 {
1594         struct batadv_tt_common_entry *tt_common_entry;
1595         struct batadv_tt_query_packet *tt_response;
1596         struct batadv_tt_change *tt_change;
1597         struct hlist_head *head;
1598         struct sk_buff *skb = NULL;
1599         uint16_t tt_tot, tt_count;
1600         ssize_t tt_query_size = sizeof(struct batadv_tt_query_packet);
1601         uint32_t i;
1602         size_t len;
1603
1604         if (tt_query_size + tt_len > bat_priv->soft_iface->mtu) {
1605                 tt_len = bat_priv->soft_iface->mtu - tt_query_size;
1606                 tt_len -= tt_len % sizeof(struct batadv_tt_change);
1607         }
1608         tt_tot = tt_len / sizeof(struct batadv_tt_change);
1609
1610         len = tt_query_size + tt_len;
1611         skb = netdev_alloc_skb_ip_align(NULL, len + ETH_HLEN);
1612         if (!skb)
1613                 goto out;
1614
1615         skb->priority = TC_PRIO_CONTROL;
1616         skb_reserve(skb, ETH_HLEN);
1617         tt_response = (struct batadv_tt_query_packet *)skb_put(skb, len);
1618         tt_response->ttvn = ttvn;
1619
1620         tt_change = (struct batadv_tt_change *)(skb->data + tt_query_size);
1621         tt_count = 0;
1622
1623         rcu_read_lock();
1624         for (i = 0; i < hash->size; i++) {
1625                 head = &hash->table[i];
1626
1627                 hlist_for_each_entry_rcu(tt_common_entry,
1628                                          head, hash_entry) {
1629                         if (tt_count == tt_tot)
1630                                 break;
1631
1632                         if ((valid_cb) && (!valid_cb(tt_common_entry, cb_data)))
1633                                 continue;
1634
1635                         memcpy(tt_change->addr, tt_common_entry->addr,
1636                                ETH_ALEN);
1637                         tt_change->flags = tt_common_entry->flags;
1638
1639                         tt_count++;
1640                         tt_change++;
1641                 }
1642         }
1643         rcu_read_unlock();
1644
1645         /* store in the message the number of entries we have successfully
1646          * copied
1647          */
1648         tt_response->tt_data = htons(tt_count);
1649
1650 out:
1651         return skb;
1652 }
1653
1654 static int batadv_send_tt_request(struct batadv_priv *bat_priv,
1655                                   struct batadv_orig_node *dst_orig_node,
1656                                   uint8_t ttvn, uint16_t tt_crc,
1657                                   bool full_table)
1658 {
1659         struct sk_buff *skb = NULL;
1660         struct batadv_tt_query_packet *tt_request;
1661         struct batadv_hard_iface *primary_if;
1662         struct batadv_tt_req_node *tt_req_node = NULL;
1663         int ret = 1;
1664         size_t tt_req_len;
1665
1666         primary_if = batadv_primary_if_get_selected(bat_priv);
1667         if (!primary_if)
1668                 goto out;
1669
1670         /* The new tt_req will be issued only if I'm not waiting for a
1671          * reply from the same orig_node yet
1672          */
1673         tt_req_node = batadv_new_tt_req_node(bat_priv, dst_orig_node);
1674         if (!tt_req_node)
1675                 goto out;
1676
1677         skb = netdev_alloc_skb_ip_align(NULL, sizeof(*tt_request) + ETH_HLEN);
1678         if (!skb)
1679                 goto out;
1680
1681         skb->priority = TC_PRIO_CONTROL;
1682         skb_reserve(skb, ETH_HLEN);
1683
1684         tt_req_len = sizeof(*tt_request);
1685         tt_request = (struct batadv_tt_query_packet *)skb_put(skb, tt_req_len);
1686
1687         tt_request->header.packet_type = BATADV_TT_QUERY;
1688         tt_request->header.version = BATADV_COMPAT_VERSION;
1689         memcpy(tt_request->src, primary_if->net_dev->dev_addr, ETH_ALEN);
1690         memcpy(tt_request->dst, dst_orig_node->orig, ETH_ALEN);
1691         tt_request->header.ttl = BATADV_TTL;
1692         tt_request->ttvn = ttvn;
1693         tt_request->tt_data = htons(tt_crc);
1694         tt_request->flags = BATADV_TT_REQUEST;
1695
1696         if (full_table)
1697                 tt_request->flags |= BATADV_TT_FULL_TABLE;
1698
1699         batadv_dbg(BATADV_DBG_TT, bat_priv, "Sending TT_REQUEST to %pM [%c]\n",
1700                    dst_orig_node->orig, (full_table ? 'F' : '.'));
1701
1702         batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_TX);
1703
1704         if (batadv_send_skb_to_orig(skb, dst_orig_node, NULL) != NET_XMIT_DROP)
1705                 ret = 0;
1706
1707 out:
1708         if (primary_if)
1709                 batadv_hardif_free_ref(primary_if);
1710         if (ret)
1711                 kfree_skb(skb);
1712         if (ret && tt_req_node) {
1713                 spin_lock_bh(&bat_priv->tt.req_list_lock);
1714                 list_del(&tt_req_node->list);
1715                 spin_unlock_bh(&bat_priv->tt.req_list_lock);
1716                 kfree(tt_req_node);
1717         }
1718         return ret;
1719 }
1720
1721 static bool
1722 batadv_send_other_tt_response(struct batadv_priv *bat_priv,
1723                               struct batadv_tt_query_packet *tt_request)
1724 {
1725         struct batadv_orig_node *req_dst_orig_node;
1726         struct batadv_orig_node *res_dst_orig_node = NULL;
1727         uint8_t orig_ttvn, req_ttvn, ttvn;
1728         int res, ret = false;
1729         unsigned char *tt_buff;
1730         bool full_table;
1731         uint16_t tt_len, tt_tot;
1732         struct sk_buff *skb = NULL;
1733         struct batadv_tt_query_packet *tt_response;
1734         uint8_t *packet_pos;
1735         size_t len;
1736
1737         batadv_dbg(BATADV_DBG_TT, bat_priv,
1738                    "Received TT_REQUEST from %pM for ttvn: %u (%pM) [%c]\n",
1739                    tt_request->src, tt_request->ttvn, tt_request->dst,
1740                    (tt_request->flags & BATADV_TT_FULL_TABLE ? 'F' : '.'));
1741
1742         /* Let's get the orig node of the REAL destination */
1743         req_dst_orig_node = batadv_orig_hash_find(bat_priv, tt_request->dst);
1744         if (!req_dst_orig_node)
1745                 goto out;
1746
1747         res_dst_orig_node = batadv_orig_hash_find(bat_priv, tt_request->src);
1748         if (!res_dst_orig_node)
1749                 goto out;
1750
1751         orig_ttvn = (uint8_t)atomic_read(&req_dst_orig_node->last_ttvn);
1752         req_ttvn = tt_request->ttvn;
1753
1754         /* I don't have the requested data */
1755         if (orig_ttvn != req_ttvn ||
1756             tt_request->tt_data != htons(req_dst_orig_node->tt_crc))
1757                 goto out;
1758
1759         /* If the full table has been explicitly requested */
1760         if (tt_request->flags & BATADV_TT_FULL_TABLE ||
1761             !req_dst_orig_node->tt_buff)
1762                 full_table = true;
1763         else
1764                 full_table = false;
1765
1766         /* In this version, fragmentation is not implemented, then
1767          * I'll send only one packet with as much TT entries as I can
1768          */
1769         if (!full_table) {
1770                 spin_lock_bh(&req_dst_orig_node->tt_buff_lock);
1771                 tt_len = req_dst_orig_node->tt_buff_len;
1772                 tt_tot = tt_len / sizeof(struct batadv_tt_change);
1773
1774                 len = sizeof(*tt_response) + tt_len;
1775                 skb = netdev_alloc_skb_ip_align(NULL, len + ETH_HLEN);
1776                 if (!skb)
1777                         goto unlock;
1778
1779                 skb->priority = TC_PRIO_CONTROL;
1780                 skb_reserve(skb, ETH_HLEN);
1781                 packet_pos = skb_put(skb, len);
1782                 tt_response = (struct batadv_tt_query_packet *)packet_pos;
1783                 tt_response->ttvn = req_ttvn;
1784                 tt_response->tt_data = htons(tt_tot);
1785
1786                 tt_buff = skb->data + sizeof(*tt_response);
1787                 /* Copy the last orig_node's OGM buffer */
1788                 memcpy(tt_buff, req_dst_orig_node->tt_buff,
1789                        req_dst_orig_node->tt_buff_len);
1790
1791                 spin_unlock_bh(&req_dst_orig_node->tt_buff_lock);
1792         } else {
1793                 tt_len = (uint16_t)atomic_read(&req_dst_orig_node->tt_size);
1794                 tt_len *= sizeof(struct batadv_tt_change);
1795                 ttvn = (uint8_t)atomic_read(&req_dst_orig_node->last_ttvn);
1796
1797                 skb = batadv_tt_response_fill_table(tt_len, ttvn,
1798                                                     bat_priv->tt.global_hash,
1799                                                     bat_priv,
1800                                                     batadv_tt_global_valid,
1801                                                     req_dst_orig_node);
1802                 if (!skb)
1803                         goto out;
1804
1805                 tt_response = (struct batadv_tt_query_packet *)skb->data;
1806         }
1807
1808         tt_response->header.packet_type = BATADV_TT_QUERY;
1809         tt_response->header.version = BATADV_COMPAT_VERSION;
1810         tt_response->header.ttl = BATADV_TTL;
1811         memcpy(tt_response->src, req_dst_orig_node->orig, ETH_ALEN);
1812         memcpy(tt_response->dst, tt_request->src, ETH_ALEN);
1813         tt_response->flags = BATADV_TT_RESPONSE;
1814
1815         if (full_table)
1816                 tt_response->flags |= BATADV_TT_FULL_TABLE;
1817
1818         batadv_dbg(BATADV_DBG_TT, bat_priv,
1819                    "Sending TT_RESPONSE %pM for %pM (ttvn: %u)\n",
1820                    res_dst_orig_node->orig, req_dst_orig_node->orig, req_ttvn);
1821
1822         batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);
1823
1824         res = batadv_send_skb_to_orig(skb, res_dst_orig_node, NULL);
1825         if (res != NET_XMIT_DROP)
1826                 ret = true;
1827
1828         goto out;
1829
1830 unlock:
1831         spin_unlock_bh(&req_dst_orig_node->tt_buff_lock);
1832
1833 out:
1834         if (res_dst_orig_node)
1835                 batadv_orig_node_free_ref(res_dst_orig_node);
1836         if (req_dst_orig_node)
1837                 batadv_orig_node_free_ref(req_dst_orig_node);
1838         if (!ret)
1839                 kfree_skb(skb);
1840         return ret;
1841 }
1842
1843 static bool
1844 batadv_send_my_tt_response(struct batadv_priv *bat_priv,
1845                            struct batadv_tt_query_packet *tt_request)
1846 {
1847         struct batadv_orig_node *orig_node;
1848         struct batadv_hard_iface *primary_if = NULL;
1849         uint8_t my_ttvn, req_ttvn, ttvn;
1850         int ret = false;
1851         unsigned char *tt_buff;
1852         bool full_table;
1853         uint16_t tt_len, tt_tot;
1854         struct sk_buff *skb = NULL;
1855         struct batadv_tt_query_packet *tt_response;
1856         uint8_t *packet_pos;
1857         size_t len;
1858
1859         batadv_dbg(BATADV_DBG_TT, bat_priv,
1860                    "Received TT_REQUEST from %pM for ttvn: %u (me) [%c]\n",
1861                    tt_request->src, tt_request->ttvn,
1862                    (tt_request->flags & BATADV_TT_FULL_TABLE ? 'F' : '.'));
1863
1864
1865         my_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
1866         req_ttvn = tt_request->ttvn;
1867
1868         orig_node = batadv_orig_hash_find(bat_priv, tt_request->src);
1869         if (!orig_node)
1870                 goto out;
1871
1872         primary_if = batadv_primary_if_get_selected(bat_priv);
1873         if (!primary_if)
1874                 goto out;
1875
1876         /* If the full table has been explicitly requested or the gap
1877          * is too big send the whole local translation table
1878          */
1879         if (tt_request->flags & BATADV_TT_FULL_TABLE || my_ttvn != req_ttvn ||
1880             !bat_priv->tt.last_changeset)
1881                 full_table = true;
1882         else
1883                 full_table = false;
1884
1885         /* In this version, fragmentation is not implemented, then
1886          * I'll send only one packet with as much TT entries as I can
1887          */
1888         if (!full_table) {
1889                 spin_lock_bh(&bat_priv->tt.last_changeset_lock);
1890                 tt_len = bat_priv->tt.last_changeset_len;
1891                 tt_tot = tt_len / sizeof(struct batadv_tt_change);
1892
1893                 len = sizeof(*tt_response) + tt_len;
1894                 skb = netdev_alloc_skb_ip_align(NULL, len + ETH_HLEN);
1895                 if (!skb)
1896                         goto unlock;
1897
1898                 skb->priority = TC_PRIO_CONTROL;
1899                 skb_reserve(skb, ETH_HLEN);
1900                 packet_pos = skb_put(skb, len);
1901                 tt_response = (struct batadv_tt_query_packet *)packet_pos;
1902                 tt_response->ttvn = req_ttvn;
1903                 tt_response->tt_data = htons(tt_tot);
1904
1905                 tt_buff = skb->data + sizeof(*tt_response);
1906                 memcpy(tt_buff, bat_priv->tt.last_changeset,
1907                        bat_priv->tt.last_changeset_len);
1908                 spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
1909         } else {
1910                 tt_len = (uint16_t)atomic_read(&bat_priv->tt.local_entry_num);
1911                 tt_len *= sizeof(struct batadv_tt_change);
1912                 ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
1913
1914                 skb = batadv_tt_response_fill_table(tt_len, ttvn,
1915                                                     bat_priv->tt.local_hash,
1916                                                     bat_priv,
1917                                                     batadv_tt_local_valid_entry,
1918                                                     NULL);
1919                 if (!skb)
1920                         goto out;
1921
1922                 tt_response = (struct batadv_tt_query_packet *)skb->data;
1923         }
1924
1925         tt_response->header.packet_type = BATADV_TT_QUERY;
1926         tt_response->header.version = BATADV_COMPAT_VERSION;
1927         tt_response->header.ttl = BATADV_TTL;
1928         memcpy(tt_response->src, primary_if->net_dev->dev_addr, ETH_ALEN);
1929         memcpy(tt_response->dst, tt_request->src, ETH_ALEN);
1930         tt_response->flags = BATADV_TT_RESPONSE;
1931
1932         if (full_table)
1933                 tt_response->flags |= BATADV_TT_FULL_TABLE;
1934
1935         batadv_dbg(BATADV_DBG_TT, bat_priv,
1936                    "Sending TT_RESPONSE to %pM [%c]\n",
1937                    orig_node->orig,
1938                    (tt_response->flags & BATADV_TT_FULL_TABLE ? 'F' : '.'));
1939
1940         batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);
1941
1942         if (batadv_send_skb_to_orig(skb, orig_node, NULL) != NET_XMIT_DROP)
1943                 ret = true;
1944         goto out;
1945
1946 unlock:
1947         spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
1948 out:
1949         if (orig_node)
1950                 batadv_orig_node_free_ref(orig_node);
1951         if (primary_if)
1952                 batadv_hardif_free_ref(primary_if);
1953         if (!ret)
1954                 kfree_skb(skb);
1955         /* This packet was for me, so it doesn't need to be re-routed */
1956         return true;
1957 }
1958
1959 bool batadv_send_tt_response(struct batadv_priv *bat_priv,
1960                              struct batadv_tt_query_packet *tt_request)
1961 {
1962         if (batadv_is_my_mac(bat_priv, tt_request->dst)) {
1963                 /* don't answer backbone gws! */
1964                 if (batadv_bla_is_backbone_gw_orig(bat_priv, tt_request->src))
1965                         return true;
1966
1967                 return batadv_send_my_tt_response(bat_priv, tt_request);
1968         } else {
1969                 return batadv_send_other_tt_response(bat_priv, tt_request);
1970         }
1971 }
1972
1973 static void _batadv_tt_update_changes(struct batadv_priv *bat_priv,
1974                                       struct batadv_orig_node *orig_node,
1975                                       struct batadv_tt_change *tt_change,
1976                                       uint16_t tt_num_changes, uint8_t ttvn)
1977 {
1978         int i;
1979         int roams;
1980
1981         for (i = 0; i < tt_num_changes; i++) {
1982                 if ((tt_change + i)->flags & BATADV_TT_CLIENT_DEL) {
1983                         roams = (tt_change + i)->flags & BATADV_TT_CLIENT_ROAM;
1984                         batadv_tt_global_del(bat_priv, orig_node,
1985                                              (tt_change + i)->addr,
1986                                              "tt removed by changes",
1987                                              roams);
1988                 } else {
1989                         if (!batadv_tt_global_add(bat_priv, orig_node,
1990                                                   (tt_change + i)->addr,
1991                                                   (tt_change + i)->flags, ttvn))
1992                                 /* In case of problem while storing a
1993                                  * global_entry, we stop the updating
1994                                  * procedure without committing the
1995                                  * ttvn change. This will avoid to send
1996                                  * corrupted data on tt_request
1997                                  */
1998                                 return;
1999                 }
2000         }
2001         orig_node->tt_initialised = true;
2002 }
2003
2004 static void batadv_tt_fill_gtable(struct batadv_priv *bat_priv,
2005                                   struct batadv_tt_query_packet *tt_response)
2006 {
2007         struct batadv_orig_node *orig_node;
2008
2009         orig_node = batadv_orig_hash_find(bat_priv, tt_response->src);
2010         if (!orig_node)
2011                 goto out;
2012
2013         /* Purge the old table first.. */
2014         batadv_tt_global_del_orig(bat_priv, orig_node, "Received full table");
2015
2016         _batadv_tt_update_changes(bat_priv, orig_node,
2017                                   (struct batadv_tt_change *)(tt_response + 1),
2018                                   ntohs(tt_response->tt_data),
2019                                   tt_response->ttvn);
2020
2021         spin_lock_bh(&orig_node->tt_buff_lock);
2022         kfree(orig_node->tt_buff);
2023         orig_node->tt_buff_len = 0;
2024         orig_node->tt_buff = NULL;
2025         spin_unlock_bh(&orig_node->tt_buff_lock);
2026
2027         atomic_set(&orig_node->last_ttvn, tt_response->ttvn);
2028
2029 out:
2030         if (orig_node)
2031                 batadv_orig_node_free_ref(orig_node);
2032 }
2033
2034 static void batadv_tt_update_changes(struct batadv_priv *bat_priv,
2035                                      struct batadv_orig_node *orig_node,
2036                                      uint16_t tt_num_changes, uint8_t ttvn,
2037                                      struct batadv_tt_change *tt_change)
2038 {
2039         _batadv_tt_update_changes(bat_priv, orig_node, tt_change,
2040                                   tt_num_changes, ttvn);
2041
2042         batadv_tt_save_orig_buffer(bat_priv, orig_node,
2043                                    (unsigned char *)tt_change, tt_num_changes);
2044         atomic_set(&orig_node->last_ttvn, ttvn);
2045 }
2046
2047 bool batadv_is_my_client(struct batadv_priv *bat_priv, const uint8_t *addr)
2048 {
2049         struct batadv_tt_local_entry *tt_local_entry;
2050         bool ret = false;
2051
2052         tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr);
2053         if (!tt_local_entry)
2054                 goto out;
2055         /* Check if the client has been logically deleted (but is kept for
2056          * consistency purpose)
2057          */
2058         if ((tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING) ||
2059             (tt_local_entry->common.flags & BATADV_TT_CLIENT_ROAM))
2060                 goto out;
2061         ret = true;
2062 out:
2063         if (tt_local_entry)
2064                 batadv_tt_local_entry_free_ref(tt_local_entry);
2065         return ret;
2066 }
2067
2068 void batadv_handle_tt_response(struct batadv_priv *bat_priv,
2069                                struct batadv_tt_query_packet *tt_response)
2070 {
2071         struct batadv_tt_req_node *node, *safe;
2072         struct batadv_orig_node *orig_node = NULL;
2073         struct batadv_tt_change *tt_change;
2074
2075         batadv_dbg(BATADV_DBG_TT, bat_priv,
2076                    "Received TT_RESPONSE from %pM for ttvn %d t_size: %d [%c]\n",
2077                    tt_response->src, tt_response->ttvn,
2078                    ntohs(tt_response->tt_data),
2079                    (tt_response->flags & BATADV_TT_FULL_TABLE ? 'F' : '.'));
2080
2081         /* we should have never asked a backbone gw */
2082         if (batadv_bla_is_backbone_gw_orig(bat_priv, tt_response->src))
2083                 goto out;
2084
2085         orig_node = batadv_orig_hash_find(bat_priv, tt_response->src);
2086         if (!orig_node)
2087                 goto out;
2088
2089         if (tt_response->flags & BATADV_TT_FULL_TABLE) {
2090                 batadv_tt_fill_gtable(bat_priv, tt_response);
2091         } else {
2092                 tt_change = (struct batadv_tt_change *)(tt_response + 1);
2093                 batadv_tt_update_changes(bat_priv, orig_node,
2094                                          ntohs(tt_response->tt_data),
2095                                          tt_response->ttvn, tt_change);
2096         }
2097
2098         /* Delete the tt_req_node from pending tt_requests list */
2099         spin_lock_bh(&bat_priv->tt.req_list_lock);
2100         list_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
2101                 if (!batadv_compare_eth(node->addr, tt_response->src))
2102                         continue;
2103                 list_del(&node->list);
2104                 kfree(node);
2105         }
2106         spin_unlock_bh(&bat_priv->tt.req_list_lock);
2107
2108         /* Recalculate the CRC for this orig_node and store it */
2109         orig_node->tt_crc = batadv_tt_global_crc(bat_priv, orig_node);
2110 out:
2111         if (orig_node)
2112                 batadv_orig_node_free_ref(orig_node);
2113 }
2114
2115 static void batadv_tt_roam_list_free(struct batadv_priv *bat_priv)
2116 {
2117         struct batadv_tt_roam_node *node, *safe;
2118
2119         spin_lock_bh(&bat_priv->tt.roam_list_lock);
2120
2121         list_for_each_entry_safe(node, safe, &bat_priv->tt.roam_list, list) {
2122                 list_del(&node->list);
2123                 kfree(node);
2124         }
2125
2126         spin_unlock_bh(&bat_priv->tt.roam_list_lock);
2127 }
2128
2129 static void batadv_tt_roam_purge(struct batadv_priv *bat_priv)
2130 {
2131         struct batadv_tt_roam_node *node, *safe;
2132
2133         spin_lock_bh(&bat_priv->tt.roam_list_lock);
2134         list_for_each_entry_safe(node, safe, &bat_priv->tt.roam_list, list) {
2135                 if (!batadv_has_timed_out(node->first_time,
2136                                           BATADV_ROAMING_MAX_TIME))
2137                         continue;
2138
2139                 list_del(&node->list);
2140                 kfree(node);
2141         }
2142         spin_unlock_bh(&bat_priv->tt.roam_list_lock);
2143 }
2144
2145 /* This function checks whether the client already reached the
2146  * maximum number of possible roaming phases. In this case the ROAMING_ADV
2147  * will not be sent.
2148  *
2149  * returns true if the ROAMING_ADV can be sent, false otherwise
2150  */
2151 static bool batadv_tt_check_roam_count(struct batadv_priv *bat_priv,
2152                                        uint8_t *client)
2153 {
2154         struct batadv_tt_roam_node *tt_roam_node;
2155         bool ret = false;
2156
2157         spin_lock_bh(&bat_priv->tt.roam_list_lock);
2158         /* The new tt_req will be issued only if I'm not waiting for a
2159          * reply from the same orig_node yet
2160          */
2161         list_for_each_entry(tt_roam_node, &bat_priv->tt.roam_list, list) {
2162                 if (!batadv_compare_eth(tt_roam_node->addr, client))
2163                         continue;
2164
2165                 if (batadv_has_timed_out(tt_roam_node->first_time,
2166                                          BATADV_ROAMING_MAX_TIME))
2167                         continue;
2168
2169                 if (!batadv_atomic_dec_not_zero(&tt_roam_node->counter))
2170                         /* Sorry, you roamed too many times! */
2171                         goto unlock;
2172                 ret = true;
2173                 break;
2174         }
2175
2176         if (!ret) {
2177                 tt_roam_node = kmalloc(sizeof(*tt_roam_node), GFP_ATOMIC);
2178                 if (!tt_roam_node)
2179                         goto unlock;
2180
2181                 tt_roam_node->first_time = jiffies;
2182                 atomic_set(&tt_roam_node->counter,
2183                            BATADV_ROAMING_MAX_COUNT - 1);
2184                 memcpy(tt_roam_node->addr, client, ETH_ALEN);
2185
2186                 list_add(&tt_roam_node->list, &bat_priv->tt.roam_list);
2187                 ret = true;
2188         }
2189
2190 unlock:
2191         spin_unlock_bh(&bat_priv->tt.roam_list_lock);
2192         return ret;
2193 }
2194
2195 static void batadv_send_roam_adv(struct batadv_priv *bat_priv, uint8_t *client,
2196                                  struct batadv_orig_node *orig_node)
2197 {
2198         struct sk_buff *skb = NULL;
2199         struct batadv_roam_adv_packet *roam_adv_packet;
2200         int ret = 1;
2201         struct batadv_hard_iface *primary_if;
2202         size_t len = sizeof(*roam_adv_packet);
2203
2204         /* before going on we have to check whether the client has
2205          * already roamed to us too many times
2206          */
2207         if (!batadv_tt_check_roam_count(bat_priv, client))
2208                 goto out;
2209
2210         skb = netdev_alloc_skb_ip_align(NULL, len + ETH_HLEN);
2211         if (!skb)
2212                 goto out;
2213
2214         skb->priority = TC_PRIO_CONTROL;
2215         skb_reserve(skb, ETH_HLEN);
2216
2217         roam_adv_packet = (struct batadv_roam_adv_packet *)skb_put(skb, len);
2218
2219         roam_adv_packet->header.packet_type = BATADV_ROAM_ADV;
2220         roam_adv_packet->header.version = BATADV_COMPAT_VERSION;
2221         roam_adv_packet->header.ttl = BATADV_TTL;
2222         roam_adv_packet->reserved = 0;
2223         primary_if = batadv_primary_if_get_selected(bat_priv);
2224         if (!primary_if)
2225                 goto out;
2226         memcpy(roam_adv_packet->src, primary_if->net_dev->dev_addr, ETH_ALEN);
2227         batadv_hardif_free_ref(primary_if);
2228         memcpy(roam_adv_packet->dst, orig_node->orig, ETH_ALEN);
2229         memcpy(roam_adv_packet->client, client, ETH_ALEN);
2230
2231         batadv_dbg(BATADV_DBG_TT, bat_priv,
2232                    "Sending ROAMING_ADV to %pM (client %pM)\n",
2233                    orig_node->orig, client);
2234
2235         batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_TX);
2236
2237         if (batadv_send_skb_to_orig(skb, orig_node, NULL) != NET_XMIT_DROP)
2238                 ret = 0;
2239
2240 out:
2241         if (ret && skb)
2242                 kfree_skb(skb);
2243         return;
2244 }
2245
2246 static void batadv_tt_purge(struct work_struct *work)
2247 {
2248         struct delayed_work *delayed_work;
2249         struct batadv_priv_tt *priv_tt;
2250         struct batadv_priv *bat_priv;
2251
2252         delayed_work = container_of(work, struct delayed_work, work);
2253         priv_tt = container_of(delayed_work, struct batadv_priv_tt, work);
2254         bat_priv = container_of(priv_tt, struct batadv_priv, tt);
2255
2256         batadv_tt_local_purge(bat_priv);
2257         batadv_tt_global_purge(bat_priv);
2258         batadv_tt_req_purge(bat_priv);
2259         batadv_tt_roam_purge(bat_priv);
2260
2261         queue_delayed_work(batadv_event_workqueue, &bat_priv->tt.work,
2262                            msecs_to_jiffies(BATADV_TT_WORK_PERIOD));
2263 }
2264
2265 void batadv_tt_free(struct batadv_priv *bat_priv)
2266 {
2267         batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_TT, 1);
2268         batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_TT, 1);
2269
2270         cancel_delayed_work_sync(&bat_priv->tt.work);
2271
2272         batadv_tt_local_table_free(bat_priv);
2273         batadv_tt_global_table_free(bat_priv);
2274         batadv_tt_req_list_free(bat_priv);
2275         batadv_tt_changes_list_free(bat_priv);
2276         batadv_tt_roam_list_free(bat_priv);
2277
2278         kfree(bat_priv->tt.last_changeset);
2279 }
2280
2281 /* This function will enable or disable the specified flags for all the entries
2282  * in the given hash table and returns the number of modified entries
2283  */
2284 static uint16_t batadv_tt_set_flags(struct batadv_hashtable *hash,
2285                                     uint16_t flags, bool enable)
2286 {
2287         uint32_t i;
2288         uint16_t changed_num = 0;
2289         struct hlist_head *head;
2290         struct batadv_tt_common_entry *tt_common_entry;
2291
2292         if (!hash)
2293                 goto out;
2294
2295         for (i = 0; i < hash->size; i++) {
2296                 head = &hash->table[i];
2297
2298                 rcu_read_lock();
2299                 hlist_for_each_entry_rcu(tt_common_entry,
2300                                          head, hash_entry) {
2301                         if (enable) {
2302                                 if ((tt_common_entry->flags & flags) == flags)
2303                                         continue;
2304                                 tt_common_entry->flags |= flags;
2305                         } else {
2306                                 if (!(tt_common_entry->flags & flags))
2307                                         continue;
2308                                 tt_common_entry->flags &= ~flags;
2309                         }
2310                         changed_num++;
2311                 }
2312                 rcu_read_unlock();
2313         }
2314 out:
2315         return changed_num;
2316 }
2317
2318 /* Purge out all the tt local entries marked with BATADV_TT_CLIENT_PENDING */
2319 static void batadv_tt_local_purge_pending_clients(struct batadv_priv *bat_priv)
2320 {
2321         struct batadv_hashtable *hash = bat_priv->tt.local_hash;
2322         struct batadv_tt_common_entry *tt_common;
2323         struct batadv_tt_local_entry *tt_local;
2324         struct hlist_node *node_tmp;
2325         struct hlist_head *head;
2326         spinlock_t *list_lock; /* protects write access to the hash lists */
2327         uint32_t i;
2328
2329         if (!hash)
2330                 return;
2331
2332         for (i = 0; i < hash->size; i++) {
2333                 head = &hash->table[i];
2334                 list_lock = &hash->list_locks[i];
2335
2336                 spin_lock_bh(list_lock);
2337                 hlist_for_each_entry_safe(tt_common, node_tmp, head,
2338                                           hash_entry) {
2339                         if (!(tt_common->flags & BATADV_TT_CLIENT_PENDING))
2340                                 continue;
2341
2342                         batadv_dbg(BATADV_DBG_TT, bat_priv,
2343                                    "Deleting local tt entry (%pM): pending\n",
2344                                    tt_common->addr);
2345
2346                         atomic_dec(&bat_priv->tt.local_entry_num);
2347                         hlist_del_rcu(&tt_common->hash_entry);
2348                         tt_local = container_of(tt_common,
2349                                                 struct batadv_tt_local_entry,
2350                                                 common);
2351                         batadv_tt_local_entry_free_ref(tt_local);
2352                 }
2353                 spin_unlock_bh(list_lock);
2354         }
2355 }
2356
2357 /**
2358  * batadv_tt_local_commit_changes - commit all pending local tt changes which
2359  *  have been queued in the time since the last commit
2360  * @bat_priv: the bat priv with all the soft interface information
2361  */
2362 void batadv_tt_local_commit_changes(struct batadv_priv *bat_priv)
2363 {
2364         uint16_t changed_num = 0;
2365
2366         if (atomic_read(&bat_priv->tt.local_changes) < 1) {
2367                 if (!batadv_atomic_dec_not_zero(&bat_priv->tt.ogm_append_cnt))
2368                         batadv_tt_tvlv_container_update(bat_priv);
2369                 return;
2370         }
2371
2372         changed_num = batadv_tt_set_flags(bat_priv->tt.local_hash,
2373                                           BATADV_TT_CLIENT_NEW, false);
2374
2375         /* all reset entries have to be counted as local entries */
2376         atomic_add(changed_num, &bat_priv->tt.local_entry_num);
2377         batadv_tt_local_purge_pending_clients(bat_priv);
2378         bat_priv->tt.local_crc = batadv_tt_local_crc(bat_priv);
2379
2380         /* Increment the TTVN only once per OGM interval */
2381         atomic_inc(&bat_priv->tt.vn);
2382         batadv_dbg(BATADV_DBG_TT, bat_priv,
2383                    "Local changes committed, updating to ttvn %u\n",
2384                    (uint8_t)atomic_read(&bat_priv->tt.vn));
2385
2386         /* reset the sending counter */
2387         atomic_set(&bat_priv->tt.ogm_append_cnt, BATADV_TT_OGM_APPEND_MAX);
2388         batadv_tt_tvlv_container_update(bat_priv);
2389 }
2390
2391 bool batadv_is_ap_isolated(struct batadv_priv *bat_priv, uint8_t *src,
2392                            uint8_t *dst)
2393 {
2394         struct batadv_tt_local_entry *tt_local_entry = NULL;
2395         struct batadv_tt_global_entry *tt_global_entry = NULL;
2396         bool ret = false;
2397
2398         if (!atomic_read(&bat_priv->ap_isolation))
2399                 goto out;
2400
2401         tt_local_entry = batadv_tt_local_hash_find(bat_priv, dst);
2402         if (!tt_local_entry)
2403                 goto out;
2404
2405         tt_global_entry = batadv_tt_global_hash_find(bat_priv, src);
2406         if (!tt_global_entry)
2407                 goto out;
2408
2409         if (!_batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
2410                 goto out;
2411
2412         ret = true;
2413
2414 out:
2415         if (tt_global_entry)
2416                 batadv_tt_global_entry_free_ref(tt_global_entry);
2417         if (tt_local_entry)
2418                 batadv_tt_local_entry_free_ref(tt_local_entry);
2419         return ret;
2420 }
2421
2422 /**
2423  * batadv_tt_update_orig - update global translation table with new tt
2424  *  information received via ogms
2425  * @bat_priv: the bat priv with all the soft interface information
2426  * @orig: the orig_node of the ogm
2427  * @tt_buff: buffer holding the tt information
2428  * @tt_num_changes: number of tt changes inside the tt buffer
2429  * @ttvn: translation table version number of this changeset
2430  * @tt_crc: crc16 checksum of orig node's translation table
2431  */
2432 static void batadv_tt_update_orig(struct batadv_priv *bat_priv,
2433                                   struct batadv_orig_node *orig_node,
2434                                   const unsigned char *tt_buff,
2435                                   uint16_t tt_num_changes, uint8_t ttvn,
2436                                   uint16_t tt_crc)
2437 {
2438         uint8_t orig_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
2439         bool full_table = true;
2440         struct batadv_tt_change *tt_change;
2441
2442         /* don't care about a backbone gateways updates. */
2443         if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig))
2444                 return;
2445
2446         /* orig table not initialised AND first diff is in the OGM OR the ttvn
2447          * increased by one -> we can apply the attached changes
2448          */
2449         if ((!orig_node->tt_initialised && ttvn == 1) ||
2450             ttvn - orig_ttvn == 1) {
2451                 /* the OGM could not contain the changes due to their size or
2452                  * because they have already been sent BATADV_TT_OGM_APPEND_MAX
2453                  * times.
2454                  * In this case send a tt request
2455                  */
2456                 if (!tt_num_changes) {
2457                         full_table = false;
2458                         goto request_table;
2459                 }
2460
2461                 tt_change = (struct batadv_tt_change *)tt_buff;
2462                 batadv_tt_update_changes(bat_priv, orig_node, tt_num_changes,
2463                                          ttvn, tt_change);
2464
2465                 /* Even if we received the precomputed crc with the OGM, we
2466                  * prefer to recompute it to spot any possible inconsistency
2467                  * in the global table
2468                  */
2469                 orig_node->tt_crc = batadv_tt_global_crc(bat_priv, orig_node);
2470
2471                 /* The ttvn alone is not enough to guarantee consistency
2472                  * because a single value could represent different states
2473                  * (due to the wrap around). Thus a node has to check whether
2474                  * the resulting table (after applying the changes) is still
2475                  * consistent or not. E.g. a node could disconnect while its
2476                  * ttvn is X and reconnect on ttvn = X + TTVN_MAX: in this case
2477                  * checking the CRC value is mandatory to detect the
2478                  * inconsistency
2479                  */
2480                 if (orig_node->tt_crc != tt_crc)
2481                         goto request_table;
2482         } else {
2483                 /* if we missed more than one change or our tables are not
2484                  * in sync anymore -> request fresh tt data
2485                  */
2486                 if (!orig_node->tt_initialised || ttvn != orig_ttvn ||
2487                     orig_node->tt_crc != tt_crc) {
2488 request_table:
2489                         batadv_dbg(BATADV_DBG_TT, bat_priv,
2490                                    "TT inconsistency for %pM. Need to retrieve the correct information (ttvn: %u last_ttvn: %u crc: %#.4x last_crc: %#.4x num_changes: %u)\n",
2491                                    orig_node->orig, ttvn, orig_ttvn, tt_crc,
2492                                    orig_node->tt_crc, tt_num_changes);
2493                         batadv_send_tt_request(bat_priv, orig_node, ttvn,
2494                                                tt_crc, full_table);
2495                         return;
2496                 }
2497         }
2498 }
2499
2500 /* returns true whether we know that the client has moved from its old
2501  * originator to another one. This entry is kept is still kept for consistency
2502  * purposes
2503  */
2504 bool batadv_tt_global_client_is_roaming(struct batadv_priv *bat_priv,
2505                                         uint8_t *addr)
2506 {
2507         struct batadv_tt_global_entry *tt_global_entry;
2508         bool ret = false;
2509
2510         tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr);
2511         if (!tt_global_entry)
2512                 goto out;
2513
2514         ret = tt_global_entry->common.flags & BATADV_TT_CLIENT_ROAM;
2515         batadv_tt_global_entry_free_ref(tt_global_entry);
2516 out:
2517         return ret;
2518 }
2519
2520 /**
2521  * batadv_tt_local_client_is_roaming - tells whether the client is roaming
2522  * @bat_priv: the bat priv with all the soft interface information
2523  * @addr: the MAC address of the local client to query
2524  *
2525  * Returns true if the local client is known to be roaming (it is not served by
2526  * this node anymore) or not. If yes, the client is still present in the table
2527  * to keep the latter consistent with the node TTVN
2528  */
2529 bool batadv_tt_local_client_is_roaming(struct batadv_priv *bat_priv,
2530                                        uint8_t *addr)
2531 {
2532         struct batadv_tt_local_entry *tt_local_entry;
2533         bool ret = false;
2534
2535         tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr);
2536         if (!tt_local_entry)
2537                 goto out;
2538
2539         ret = tt_local_entry->common.flags & BATADV_TT_CLIENT_ROAM;
2540         batadv_tt_local_entry_free_ref(tt_local_entry);
2541 out:
2542         return ret;
2543 }
2544
2545 bool batadv_tt_add_temporary_global_entry(struct batadv_priv *bat_priv,
2546                                           struct batadv_orig_node *orig_node,
2547                                           const unsigned char *addr)
2548 {
2549         bool ret = false;
2550
2551         /* if the originator is a backbone node (meaning it belongs to the same
2552          * LAN of this node) the temporary client must not be added because to
2553          * reach such destination the node must use the LAN instead of the mesh
2554          */
2555         if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig))
2556                 goto out;
2557
2558         if (!batadv_tt_global_add(bat_priv, orig_node, addr,
2559                                   BATADV_TT_CLIENT_TEMP,
2560                                   atomic_read(&orig_node->last_ttvn)))
2561                 goto out;
2562
2563         batadv_dbg(BATADV_DBG_TT, bat_priv,
2564                    "Added temporary global client (addr: %pM orig: %pM)\n",
2565                    addr, orig_node->orig);
2566         ret = true;
2567 out:
2568         return ret;
2569 }
2570
2571 /**
2572  * batadv_tt_tvlv_ogm_handler_v1 - process incoming tt tvlv container
2573  * @bat_priv: the bat priv with all the soft interface information
2574  * @orig: the orig_node of the ogm
2575  * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
2576  * @tvlv_value: tvlv buffer containing the gateway data
2577  * @tvlv_value_len: tvlv buffer length
2578  */
2579 static void batadv_tt_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
2580                                           struct batadv_orig_node *orig,
2581                                           uint8_t flags,
2582                                           void *tvlv_value,
2583                                           uint16_t tvlv_value_len)
2584 {
2585         struct batadv_tvlv_tt_data *tt_data;
2586         uint16_t num_entries;
2587
2588         if (tvlv_value_len < sizeof(*tt_data))
2589                 return;
2590
2591         tt_data = (struct batadv_tvlv_tt_data *)tvlv_value;
2592         tvlv_value_len -= sizeof(*tt_data);
2593
2594         num_entries = tvlv_value_len / batadv_tt_len(1);
2595
2596         batadv_tt_update_orig(bat_priv, orig,
2597                               (unsigned char *)(tt_data + 1),
2598                               num_entries, tt_data->ttvn, ntohs(tt_data->crc));
2599 }
2600
2601 /**
2602  * batadv_tt_init - initialise the translation table internals
2603  * @bat_priv: the bat priv with all the soft interface information
2604  *
2605  * Return 0 on success or negative error number in case of failure.
2606  */
2607 int batadv_tt_init(struct batadv_priv *bat_priv)
2608 {
2609         int ret;
2610
2611         ret = batadv_tt_local_init(bat_priv);
2612         if (ret < 0)
2613                 return ret;
2614
2615         ret = batadv_tt_global_init(bat_priv);
2616         if (ret < 0)
2617                 return ret;
2618
2619         batadv_tvlv_handler_register(bat_priv, batadv_tt_tvlv_ogm_handler_v1,
2620                                      NULL, BATADV_TVLV_TT, 1, BATADV_NO_FLAGS);
2621
2622         INIT_DELAYED_WORK(&bat_priv->tt.work, batadv_tt_purge);
2623         queue_delayed_work(batadv_event_workqueue, &bat_priv->tt.work,
2624                            msecs_to_jiffies(BATADV_TT_WORK_PERIOD));
2625
2626         return 1;
2627 }