net/batman-adv/vis.c

   1 /* Copyright (C) 2008-2012 B.A.T.M.A.N. contributors:
   2  *
   3  * Simon Wunderlich
   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 "send.h"
  22 #include "translation-table.h"
  23 #include "vis.h"
  24 #include "soft-interface.h"
  25 #include "hard-interface.h"
  26 #include "hash.h"
  27 #include "originator.h"
  28
  29 #define BATADV_MAX_VIS_PACKET_SIZE 1000
  30
  31 /* hash class keys */
  32 static struct lock_class_key batadv_vis_hash_lock_class_key;
  33
  34 static void batadv_start_vis_timer(struct batadv_priv *bat_priv);
  35
  36 /* free the info */
  37 static void batadv_free_info(struct kref *ref)
  38 {
  39         struct batadv_vis_info *info;
  40         struct batadv_priv *bat_priv;
  41         struct batadv_recvlist_node *entry, *tmp;
  42
  43         info = container_of(ref, struct batadv_vis_info, refcount);
  44         bat_priv = info->bat_priv;
  45
  46         list_del_init(&info->send_list);
  47         spin_lock_bh(&bat_priv->vis.list_lock);
  48         list_for_each_entry_safe(entry, tmp, &info->recv_list, list) {
  49                 list_del(&entry->list);
  50                 kfree(entry);
  51         }
  52
  53         spin_unlock_bh(&bat_priv->vis.list_lock);
  54         kfree_skb(info->skb_packet);
  55         kfree(info);
  56 }
  57
  58 /* Compare two vis packets, used by the hashing algorithm */
  59 static int batadv_vis_info_cmp(const struct hlist_node *node, const void *data2)
  60 {
  61         const struct batadv_vis_info *d1, *d2;
  62         const struct batadv_vis_packet *p1, *p2;
  63
  64         d1 = container_of(node, struct batadv_vis_info, hash_entry);
  65         d2 = data2;
  66         p1 = (struct batadv_vis_packet *)d1->skb_packet->data;
  67         p2 = (struct batadv_vis_packet *)d2->skb_packet->data;
  68         return batadv_compare_eth(p1->vis_orig, p2->vis_orig);
  69 }
  70
  71 /* hash function to choose an entry in a hash table of given size
  72  * hash algorithm from http://en.wikipedia.org/wiki/Hash_table
  73  */
  74 static uint32_t batadv_vis_info_choose(const void *data, uint32_t size)
  75 {
  76         const struct batadv_vis_info *vis_info = data;
  77         const struct batadv_vis_packet *packet;
  78         const unsigned char *key;
  79         uint32_t hash = 0;
  80         size_t i;
  81
  82         packet = (struct batadv_vis_packet *)vis_info->skb_packet->data;
  83         key = packet->vis_orig;
  84         for (i = 0; i < ETH_ALEN; i++) {
  85                 hash += key[i];
  86                 hash += (hash << 10);
  87                 hash ^= (hash >> 6);
  88         }
  89
  90         hash += (hash << 3);
  91         hash ^= (hash >> 11);
  92         hash += (hash << 15);
  93
  94         return hash % size;
  95 }
  96
  97 static struct batadv_vis_info *
  98 batadv_vis_hash_find(struct batadv_priv *bat_priv, const void *data)
  99 {
 100         struct batadv_hashtable *hash = bat_priv->vis.hash;
 101         struct hlist_head *head;
 102         struct hlist_node *node;
 103         struct batadv_vis_info *vis_info, *vis_info_tmp = NULL;
 104         uint32_t index;
 105
 106         if (!hash)
 107                 return NULL;
 108
 109         index = batadv_vis_info_choose(data, hash->size);
 110         head = &hash->table[index];
 111
 112         rcu_read_lock();
 113         hlist_for_each_entry_rcu(vis_info, node, head, hash_entry) {
 114                 if (!batadv_vis_info_cmp(node, data))
 115                         continue;
 116
 117                 vis_info_tmp = vis_info;
 118                 break;
 119         }
 120         rcu_read_unlock();
 121
 122         return vis_info_tmp;
 123 }
 124
 125 /* insert interface to the list of interfaces of one originator, if it
 126  * does not already exist in the list
 127  */
 128 static void batadv_vis_data_insert_interface(const uint8_t *interface,
 129                                              struct hlist_head *if_list,
 130                                              bool primary)
 131 {
 132         struct batadv_if_list_entry *entry;
 133         struct hlist_node *pos;
 134
 135         hlist_for_each_entry(entry, pos, if_list, list) {
 136                 if (batadv_compare_eth(entry->addr, interface))
 137                         return;
 138         }
 139
 140         /* it's a new address, add it to the list */
 141         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
 142         if (!entry)
 143                 return;
 144         memcpy(entry->addr, interface, ETH_ALEN);
 145         entry->primary = primary;
 146         hlist_add_head(&entry->list, if_list);
 147 }
 148
 149 static void batadv_vis_data_read_prim_sec(struct seq_file *seq,
 150                                           const struct hlist_head *if_list)
 151 {
 152         struct batadv_if_list_entry *entry;
 153         struct hlist_node *pos;
 154
 155         hlist_for_each_entry(entry, pos, if_list, list) {
 156                 if (entry->primary)
 157                         seq_printf(seq, "PRIMARY, ");
 158                 else
 159                         seq_printf(seq,  "SEC %pM, ", entry->addr);
 160         }
 161 }
 162
 163 /* read an entry  */
 164 static ssize_t
 165 batadv_vis_data_read_entry(struct seq_file *seq,
 166                            const struct batadv_vis_info_entry *entry,
 167                            const uint8_t *src, bool primary)
 168 {
 169         if (primary && entry->quality == 0)
 170                 return seq_printf(seq, "TT %pM, ", entry->dest);
 171         else if (batadv_compare_eth(entry->src, src))
 172                 return seq_printf(seq, "TQ %pM %d, ", entry->dest,
 173                                   entry->quality);
 174
 175         return 0;
 176 }
 177
 178 static void
 179 batadv_vis_data_insert_interfaces(struct hlist_head *list,
 180                                   struct batadv_vis_packet *packet,
 181                                   struct batadv_vis_info_entry *entries)
 182 {
 183         int i;
 184
 185         for (i = 0; i < packet->entries; i++) {
 186                 if (entries[i].quality == 0)
 187                         continue;
 188
 189                 if (batadv_compare_eth(entries[i].src, packet->vis_orig))
 190                         continue;
 191
 192                 batadv_vis_data_insert_interface(entries[i].src, list, false);
 193         }
 194 }
 195
 196 static void batadv_vis_data_read_entries(struct seq_file *seq,
 197                                          struct hlist_head *list,
 198                                          struct batadv_vis_packet *packet,
 199                                          struct batadv_vis_info_entry *entries)
 200 {
 201         int i;
 202         struct batadv_if_list_entry *entry;
 203         struct hlist_node *pos;
 204
 205         hlist_for_each_entry(entry, pos, list, list) {
 206                 seq_printf(seq, "%pM,", entry->addr);
 207
 208                 for (i = 0; i < packet->entries; i++)
 209                         batadv_vis_data_read_entry(seq, &entries[i],
 210                                                    entry->addr, entry->primary);
 211
 212                 /* add primary/secondary records */
 213                 if (batadv_compare_eth(entry->addr, packet->vis_orig))
 214                         batadv_vis_data_read_prim_sec(seq, list);
 215
 216                 seq_printf(seq, "\n");
 217         }
 218 }
 219
 220 static void batadv_vis_seq_print_text_bucket(struct seq_file *seq,
 221                                              const struct hlist_head *head)
 222 {
 223         struct hlist_node *node;
 224         struct batadv_vis_info *info;
 225         struct batadv_vis_packet *packet;
 226         uint8_t *entries_pos;
 227         struct batadv_vis_info_entry *entries;
 228         struct batadv_if_list_entry *entry;
 229         struct hlist_node *pos, *n;
 230
 231         HLIST_HEAD(vis_if_list);
 232
 233         hlist_for_each_entry_rcu(info, node, head, hash_entry) {
 234                 packet = (struct batadv_vis_packet *)info->skb_packet->data;
 235                 entries_pos = (uint8_t *)packet + sizeof(*packet);
 236                 entries = (struct batadv_vis_info_entry *)entries_pos;
 237
 238                 batadv_vis_data_insert_interface(packet->vis_orig, &vis_if_list,
 239                                                  true);
 240                 batadv_vis_data_insert_interfaces(&vis_if_list, packet,
 241                                                   entries);
 242                 batadv_vis_data_read_entries(seq, &vis_if_list, packet,
 243                                              entries);
 244
 245                 hlist_for_each_entry_safe(entry, pos, n, &vis_if_list, list) {
 246                         hlist_del(&entry->list);
 247                         kfree(entry);
 248                 }
 249         }
 250 }
 251
 252 int batadv_vis_seq_print_text(struct seq_file *seq, void *offset)
 253 {
 254         struct batadv_hard_iface *primary_if;
 255         struct hlist_head *head;
 256         struct net_device *net_dev = (struct net_device *)seq->private;
 257         struct batadv_priv *bat_priv = netdev_priv(net_dev);
 258         struct batadv_hashtable *hash = bat_priv->vis.hash;
 259         uint32_t i;
 260         int ret = 0;
 261         int vis_server = atomic_read(&bat_priv->vis_mode);
 262
 263         primary_if = batadv_primary_if_get_selected(bat_priv);
 264         if (!primary_if)
 265                 goto out;
 266
 267         if (vis_server == BATADV_VIS_TYPE_CLIENT_UPDATE)
 268                 goto out;
 269
 270         spin_lock_bh(&bat_priv->vis.hash_lock);
 271         for (i = 0; i < hash->size; i++) {
 272                 head = &hash->table[i];
 273                 batadv_vis_seq_print_text_bucket(seq, head);
 274         }
 275         spin_unlock_bh(&bat_priv->vis.hash_lock);
 276
 277 out:
 278         if (primary_if)
 279                 batadv_hardif_free_ref(primary_if);
 280         return ret;
 281 }
 282
 283 /* add the info packet to the send list, if it was not
 284  * already linked in.
 285  */
 286 static void batadv_send_list_add(struct batadv_priv *bat_priv,
 287                                  struct batadv_vis_info *info)
 288 {
 289         if (list_empty(&info->send_list)) {
 290                 kref_get(&info->refcount);
 291                 list_add_tail(&info->send_list, &bat_priv->vis.send_list);
 292         }
 293 }
 294
 295 /* delete the info packet from the send list, if it was
 296  * linked in.
 297  */
 298 static void batadv_send_list_del(struct batadv_vis_info *info)
 299 {
 300         if (!list_empty(&info->send_list)) {
 301                 list_del_init(&info->send_list);
 302                 kref_put(&info->refcount, batadv_free_info);
 303         }
 304 }
 305
 306 /* tries to add one entry to the receive list. */
 307 static void batadv_recv_list_add(struct batadv_priv *bat_priv,
 308                                  struct list_head *recv_list, const char *mac)
 309 {
 310         struct batadv_recvlist_node *entry;
 311
 312         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
 313         if (!entry)
 314                 return;
 315
 316         memcpy(entry->mac, mac, ETH_ALEN);
 317         spin_lock_bh(&bat_priv->vis.list_lock);
 318         list_add_tail(&entry->list, recv_list);
 319         spin_unlock_bh(&bat_priv->vis.list_lock);
 320 }
 321
 322 /* returns 1 if this mac is in the recv_list */
 323 static int batadv_recv_list_is_in(struct batadv_priv *bat_priv,
 324                                   const struct list_head *recv_list,
 325                                   const char *mac)
 326 {
 327         const struct batadv_recvlist_node *entry;
 328
 329         spin_lock_bh(&bat_priv->vis.list_lock);
 330         list_for_each_entry(entry, recv_list, list) {
 331                 if (batadv_compare_eth(entry->mac, mac)) {
 332                         spin_unlock_bh(&bat_priv->vis.list_lock);
 333                         return 1;
 334                 }
 335         }
 336         spin_unlock_bh(&bat_priv->vis.list_lock);
 337         return 0;
 338 }
 339
 340 /* try to add the packet to the vis_hash. return NULL if invalid (e.g. too old,
 341  * broken.. ).  vis hash must be locked outside.  is_new is set when the packet
 342  * is newer than old entries in the hash.
 343  */
 344 static struct batadv_vis_info *
 345 batadv_add_packet(struct batadv_priv *bat_priv,
 346                   struct batadv_vis_packet *vis_packet, int vis_info_len,
 347                   int *is_new, int make_broadcast)
 348 {
 349         struct batadv_vis_info *info, *old_info;
 350         struct batadv_vis_packet *search_packet, *old_packet;
 351         struct batadv_vis_info search_elem;
 352         struct batadv_vis_packet *packet;
 353         struct sk_buff *tmp_skb;
 354         int hash_added;
 355         size_t len;
 356         size_t max_entries;
 357
 358         *is_new = 0;
 359         /* sanity check */
 360         if (!bat_priv->vis.hash)
 361                 return NULL;
 362
 363         /* see if the packet is already in vis_hash */
 364         search_elem.skb_packet = dev_alloc_skb(sizeof(*search_packet));
 365         if (!search_elem.skb_packet)
 366                 return NULL;
 367         len = sizeof(*search_packet);
 368         tmp_skb = search_elem.skb_packet;
 369         search_packet = (struct batadv_vis_packet *)skb_put(tmp_skb, len);
 370
 371         memcpy(search_packet->vis_orig, vis_packet->vis_orig, ETH_ALEN);
 372         old_info = batadv_vis_hash_find(bat_priv, &search_elem);
 373         kfree_skb(search_elem.skb_packet);
 374
 375         if (old_info) {
 376                 tmp_skb = old_info->skb_packet;
 377                 old_packet = (struct batadv_vis_packet *)tmp_skb->data;
 378                 if (!batadv_seq_after(ntohl(vis_packet->seqno),
 379                                       ntohl(old_packet->seqno))) {
 380                         if (old_packet->seqno == vis_packet->seqno) {
 381                                 batadv_recv_list_add(bat_priv,
 382                                                      &old_info->recv_list,
 383                                                      vis_packet->sender_orig);
 384                                 return old_info;
 385                         } else {
 386                                 /* newer packet is already in hash. */
 387                                 return NULL;
 388                         }
 389                 }
 390                 /* remove old entry */
 391                 batadv_hash_remove(bat_priv->vis.hash, batadv_vis_info_cmp,
 392                                    batadv_vis_info_choose, old_info);
 393                 batadv_send_list_del(old_info);
 394                 kref_put(&old_info->refcount, batadv_free_info);
 395         }
 396
 397         info = kmalloc(sizeof(*info), GFP_ATOMIC);
 398         if (!info)
 399                 return NULL;
 400
 401         len = sizeof(*packet) + vis_info_len;
 402         info->skb_packet = dev_alloc_skb(len + ETH_HLEN + NET_IP_ALIGN);
 403         if (!info->skb_packet) {
 404                 kfree(info);
 405                 return NULL;
 406         }
 407         skb_reserve(info->skb_packet, ETH_HLEN + NET_IP_ALIGN);
 408         packet = (struct batadv_vis_packet *)skb_put(info->skb_packet, len);
 409
 410         kref_init(&info->refcount);
 411         INIT_LIST_HEAD(&info->send_list);
 412         INIT_LIST_HEAD(&info->recv_list);
 413         info->first_seen = jiffies;
 414         info->bat_priv = bat_priv;
 415         memcpy(packet, vis_packet, len);
 416
 417         /* initialize and add new packet. */
 418         *is_new = 1;
 419
 420         /* Make it a broadcast packet, if required */
 421         if (make_broadcast)
 422                 memcpy(packet->target_orig, batadv_broadcast_addr, ETH_ALEN);
 423
 424         /* repair if entries is longer than packet. */
 425         max_entries = vis_info_len / sizeof(struct batadv_vis_info_entry);
 426         if (packet->entries > max_entries)
 427                 packet->entries = max_entries;
 428
 429         batadv_recv_list_add(bat_priv, &info->recv_list, packet->sender_orig);
 430
 431         /* try to add it */
 432         hash_added = batadv_hash_add(bat_priv->vis.hash, batadv_vis_info_cmp,
 433                                      batadv_vis_info_choose, info,
 434                                      &info->hash_entry);
 435         if (hash_added != 0) {
 436                 /* did not work (for some reason) */
 437                 kref_put(&info->refcount, batadv_free_info);
 438                 info = NULL;
 439         }
 440
 441         return info;
 442 }
 443
 444 /* handle the server sync packet, forward if needed. */
 445 void batadv_receive_server_sync_packet(struct batadv_priv *bat_priv,
 446                                        struct batadv_vis_packet *vis_packet,
 447                                        int vis_info_len)
 448 {
 449         struct batadv_vis_info *info;
 450         int is_new, make_broadcast;
 451         int vis_server = atomic_read(&bat_priv->vis_mode);
 452
 453         make_broadcast = (vis_server == BATADV_VIS_TYPE_SERVER_SYNC);
 454
 455         spin_lock_bh(&bat_priv->vis.hash_lock);
 456         info = batadv_add_packet(bat_priv, vis_packet, vis_info_len,
 457                                  &is_new, make_broadcast);
 458         if (!info)
 459                 goto end;
 460
 461         /* only if we are server ourselves and packet is newer than the one in
 462          * hash.
 463          */
 464         if (vis_server == BATADV_VIS_TYPE_SERVER_SYNC && is_new)
 465                 batadv_send_list_add(bat_priv, info);
 466 end:
 467         spin_unlock_bh(&bat_priv->vis.hash_lock);
 468 }
 469
 470 /* handle an incoming client update packet and schedule forward if needed. */
 471 void batadv_receive_client_update_packet(struct batadv_priv *bat_priv,
 472                                          struct batadv_vis_packet *vis_packet,
 473                                          int vis_info_len)
 474 {
 475         struct batadv_vis_info *info;
 476         struct batadv_vis_packet *packet;
 477         int is_new;
 478         int vis_server = atomic_read(&bat_priv->vis_mode);
 479         int are_target = 0;
 480
 481         /* clients shall not broadcast. */
 482         if (is_broadcast_ether_addr(vis_packet->target_orig))
 483                 return;
 484
 485         /* Are we the target for this VIS packet? */
 486         if (vis_server == BATADV_VIS_TYPE_SERVER_SYNC   &&
 487             batadv_is_my_mac(vis_packet->target_orig))
 488                 are_target = 1;
 489
 490         spin_lock_bh(&bat_priv->vis.hash_lock);
 491         info = batadv_add_packet(bat_priv, vis_packet, vis_info_len,
 492                                  &is_new, are_target);
 493
 494         if (!info)
 495                 goto end;
 496         /* note that outdated packets will be dropped at this point. */
 497
 498         packet = (struct batadv_vis_packet *)info->skb_packet->data;
 499
 500         /* send only if we're the target server or ... */
 501         if (are_target && is_new) {
 502                 packet->vis_type = BATADV_VIS_TYPE_SERVER_SYNC; /* upgrade! */
 503                 batadv_send_list_add(bat_priv, info);
 504
 505                 /* ... we're not the recipient (and thus need to forward). */
 506         } else if (!batadv_is_my_mac(packet->target_orig)) {
 507                 batadv_send_list_add(bat_priv, info);
 508         }
 509
 510 end:
 511         spin_unlock_bh(&bat_priv->vis.hash_lock);
 512 }
 513
 514 /* Walk the originators and find the VIS server with the best tq. Set the packet
 515  * address to its address and return the best_tq.
 516  *
 517  * Must be called with the originator hash locked
 518  */
 519 static int batadv_find_best_vis_server(struct batadv_priv *bat_priv,
 520                                        struct batadv_vis_info *info)
 521 {
 522         struct batadv_hashtable *hash = bat_priv->orig_hash;
 523         struct batadv_neigh_node *router;
 524         struct hlist_node *node;
 525         struct hlist_head *head;
 526         struct batadv_orig_node *orig_node;
 527         struct batadv_vis_packet *packet;
 528         int best_tq = -1;
 529         uint32_t i;
 530
 531         packet = (struct batadv_vis_packet *)info->skb_packet->data;
 532
 533         for (i = 0; i < hash->size; i++) {
 534                 head = &hash->table[i];
 535
 536                 rcu_read_lock();
 537                 hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
 538                         router = batadv_orig_node_get_router(orig_node);
 539                         if (!router)
 540                                 continue;
 541
 542                         if ((orig_node->flags & BATADV_VIS_SERVER) &&
 543                             (router->tq_avg > best_tq)) {
 544                                 best_tq = router->tq_avg;
 545                                 memcpy(packet->target_orig, orig_node->orig,
 546                                        ETH_ALEN);
 547                         }
 548                         batadv_neigh_node_free_ref(router);
 549                 }
 550                 rcu_read_unlock();
 551         }
 552
 553         return best_tq;
 554 }
 555
 556 /* Return true if the vis packet is full. */
 557 static bool batadv_vis_packet_full(const struct batadv_vis_info *info)
 558 {
 559         const struct batadv_vis_packet *packet;
 560         size_t num;
 561
 562         packet = (struct batadv_vis_packet *)info->skb_packet->data;
 563         num = BATADV_MAX_VIS_PACKET_SIZE / sizeof(struct batadv_vis_info_entry);
 564
 565         if (num < packet->entries + 1)
 566                 return true;
 567         return false;
 568 }
 569
 570 /* generates a packet of own vis data,
 571  * returns 0 on success, -1 if no packet could be generated
 572  */
 573 static int batadv_generate_vis_packet(struct batadv_priv *bat_priv)
 574 {
 575         struct batadv_hashtable *hash = bat_priv->orig_hash;
 576         struct hlist_node *node;
 577         struct hlist_head *head;
 578         struct batadv_orig_node *orig_node;
 579         struct batadv_neigh_node *router;
 580         struct batadv_vis_info *info = bat_priv->vis.my_info;
 581         struct batadv_vis_packet *packet;
 582         struct batadv_vis_info_entry *entry;
 583         struct batadv_tt_common_entry *tt_common_entry;
 584         uint8_t *packet_pos;
 585         int best_tq = -1;
 586         uint32_t i;
 587
 588         info->first_seen = jiffies;
 589         packet = (struct batadv_vis_packet *)info->skb_packet->data;
 590         packet->vis_type = atomic_read(&bat_priv->vis_mode);
 591
 592         memcpy(packet->target_orig, batadv_broadcast_addr, ETH_ALEN);
 593         packet->header.ttl = BATADV_TTL;
 594         packet->seqno = htonl(ntohl(packet->seqno) + 1);
 595         packet->entries = 0;
 596         packet->reserved = 0;
 597         skb_trim(info->skb_packet, sizeof(*packet));
 598
 599         if (packet->vis_type == BATADV_VIS_TYPE_CLIENT_UPDATE) {
 600                 best_tq = batadv_find_best_vis_server(bat_priv, info);
 601
 602                 if (best_tq < 0)
 603                         return best_tq;
 604         }
 605
 606         for (i = 0; i < hash->size; i++) {
 607                 head = &hash->table[i];
 608
 609                 rcu_read_lock();
 610                 hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
 611                         router = batadv_orig_node_get_router(orig_node);
 612                         if (!router)
 613                                 continue;
 614
 615                         if (!batadv_compare_eth(router->addr, orig_node->orig))
 616                                 goto next;
 617
 618                         if (router->if_incoming->if_status != BATADV_IF_ACTIVE)
 619                                 goto next;
 620
 621                         if (router->tq_avg < 1)
 622                                 goto next;
 623
 624                         /* fill one entry into buffer. */
 625                         packet_pos = skb_put(info->skb_packet, sizeof(*entry));
 626                         entry = (struct batadv_vis_info_entry *)packet_pos;
 627                         memcpy(entry->src,
 628                                router->if_incoming->net_dev->dev_addr,
 629                                ETH_ALEN);
 630                         memcpy(entry->dest, orig_node->orig, ETH_ALEN);
 631                         entry->quality = router->tq_avg;
 632                         packet->entries++;
 633
 634 next:
 635                         batadv_neigh_node_free_ref(router);
 636
 637                         if (batadv_vis_packet_full(info))
 638                                 goto unlock;
 639                 }
 640                 rcu_read_unlock();
 641         }
 642
 643         hash = bat_priv->tt.local_hash;
 644
 645         for (i = 0; i < hash->size; i++) {
 646                 head = &hash->table[i];
 647
 648                 rcu_read_lock();
 649                 hlist_for_each_entry_rcu(tt_common_entry, node, head,
 650                                          hash_entry) {
 651                         packet_pos = skb_put(info->skb_packet, sizeof(*entry));
 652                         entry = (struct batadv_vis_info_entry *)packet_pos;
 653                         memset(entry->src, 0, ETH_ALEN);
 654                         memcpy(entry->dest, tt_common_entry->addr, ETH_ALEN);
 655                         entry->quality = 0; /* 0 means TT */
 656                         packet->entries++;
 657
 658                         if (batadv_vis_packet_full(info))
 659                                 goto unlock;
 660                 }
 661                 rcu_read_unlock();
 662         }
 663
 664         return 0;
 665
 666 unlock:
 667         rcu_read_unlock();
 668         return 0;
 669 }
 670
 671 /* free old vis packets. Must be called with this vis_hash_lock
 672  * held
 673  */
 674 static void batadv_purge_vis_packets(struct batadv_priv *bat_priv)
 675 {
 676         uint32_t i;
 677         struct batadv_hashtable *hash = bat_priv->vis.hash;
 678         struct hlist_node *node, *node_tmp;
 679         struct hlist_head *head;
 680         struct batadv_vis_info *info;
 681
 682         for (i = 0; i < hash->size; i++) {
 683                 head = &hash->table[i];
 684
 685                 hlist_for_each_entry_safe(info, node, node_tmp,
 686                                           head, hash_entry) {
 687                         /* never purge own data. */
 688                         if (info == bat_priv->vis.my_info)
 689                                 continue;
 690
 691                         if (batadv_has_timed_out(info->first_seen,
 692                                                  BATADV_VIS_TIMEOUT)) {
 693                                 hlist_del(node);
 694                                 batadv_send_list_del(info);
 695                                 kref_put(&info->refcount, batadv_free_info);
 696                         }
 697                 }
 698         }
 699 }
 700
 701 static void batadv_broadcast_vis_packet(struct batadv_priv *bat_priv,
 702                                         struct batadv_vis_info *info)
 703 {
 704         struct batadv_hashtable *hash = bat_priv->orig_hash;
 705         struct hlist_node *node;
 706         struct hlist_head *head;
 707         struct batadv_orig_node *orig_node;
 708         struct batadv_vis_packet *packet;
 709         struct sk_buff *skb;
 710         uint32_t i;
 711
 712
 713         packet = (struct batadv_vis_packet *)info->skb_packet->data;
 714
 715         /* send to all routers in range. */
 716         for (i = 0; i < hash->size; i++) {
 717                 head = &hash->table[i];
 718
 719                 rcu_read_lock();
 720                 hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
 721                         /* if it's a vis server and reachable, send it. */
 722                         if (!(orig_node->flags & BATADV_VIS_SERVER))
 723                                 continue;
 724
 725                         /* don't send it if we already received the packet from
 726                          * this node.
 727                          */
 728                         if (batadv_recv_list_is_in(bat_priv, &info->recv_list,
 729                                                    orig_node->orig))
 730                                 continue;
 731
 732                         memcpy(packet->target_orig, orig_node->orig, ETH_ALEN);
 733                         skb = skb_clone(info->skb_packet, GFP_ATOMIC);
 734                         if (!skb)
 735                                 continue;
 736
 737                         if (!batadv_send_skb_to_orig(skb, orig_node, NULL))
 738                                 kfree_skb(skb);
 739                 }
 740                 rcu_read_unlock();
 741         }
 742 }
 743
 744 static void batadv_unicast_vis_packet(struct batadv_priv *bat_priv,
 745                                       struct batadv_vis_info *info)
 746 {
 747         struct batadv_orig_node *orig_node;
 748         struct sk_buff *skb;
 749         struct batadv_vis_packet *packet;
 750
 751         packet = (struct batadv_vis_packet *)info->skb_packet->data;
 752
 753         orig_node = batadv_orig_hash_find(bat_priv, packet->target_orig);
 754         if (!orig_node)
 755                 goto out;
 756
 757         skb = skb_clone(info->skb_packet, GFP_ATOMIC);
 758         if (!skb)
 759                 goto out;
 760
 761         if (!batadv_send_skb_to_orig(skb, orig_node, NULL))
 762                 kfree_skb(skb);
 763
 764 out:
 765         if (orig_node)
 766                 batadv_orig_node_free_ref(orig_node);
 767 }
 768
 769 /* only send one vis packet. called from batadv_send_vis_packets() */
 770 static void batadv_send_vis_packet(struct batadv_priv *bat_priv,
 771                                    struct batadv_vis_info *info)
 772 {
 773         struct batadv_hard_iface *primary_if;
 774         struct batadv_vis_packet *packet;
 775
 776         primary_if = batadv_primary_if_get_selected(bat_priv);
 777         if (!primary_if)
 778                 goto out;
 779
 780         packet = (struct batadv_vis_packet *)info->skb_packet->data;
 781         if (packet->header.ttl < 2) {
 782                 pr_debug("Error - can't send vis packet: ttl exceeded\n");
 783                 goto out;
 784         }
 785
 786         memcpy(packet->sender_orig, primary_if->net_dev->dev_addr, ETH_ALEN);
 787         packet->header.ttl--;
 788
 789         if (is_broadcast_ether_addr(packet->target_orig))
 790                 batadv_broadcast_vis_packet(bat_priv, info);
 791         else
 792                 batadv_unicast_vis_packet(bat_priv, info);
 793         packet->header.ttl++; /* restore TTL */
 794
 795 out:
 796         if (primary_if)
 797                 batadv_hardif_free_ref(primary_if);
 798 }
 799
 800 /* called from timer; send (and maybe generate) vis packet. */
 801 static void batadv_send_vis_packets(struct work_struct *work)
 802 {
 803         struct delayed_work *delayed_work;
 804         struct batadv_priv *bat_priv;
 805         struct batadv_priv_vis *priv_vis;
 806         struct batadv_vis_info *info;
 807
 808         delayed_work = container_of(work, struct delayed_work, work);
 809         priv_vis = container_of(delayed_work, struct batadv_priv_vis, work);
 810         bat_priv = container_of(priv_vis, struct batadv_priv, vis);
 811         spin_lock_bh(&bat_priv->vis.hash_lock);
 812         batadv_purge_vis_packets(bat_priv);
 813
 814         if (batadv_generate_vis_packet(bat_priv) == 0) {
 815                 /* schedule if generation was successful */
 816                 batadv_send_list_add(bat_priv, bat_priv->vis.my_info);
 817         }
 818
 819         while (!list_empty(&bat_priv->vis.send_list)) {
 820                 info = list_first_entry(&bat_priv->vis.send_list,
 821                                         typeof(*info), send_list);
 822
 823                 kref_get(&info->refcount);
 824                 spin_unlock_bh(&bat_priv->vis.hash_lock);
 825
 826                 batadv_send_vis_packet(bat_priv, info);
 827
 828                 spin_lock_bh(&bat_priv->vis.hash_lock);
 829                 batadv_send_list_del(info);
 830                 kref_put(&info->refcount, batadv_free_info);
 831         }
 832         spin_unlock_bh(&bat_priv->vis.hash_lock);
 833         batadv_start_vis_timer(bat_priv);
 834 }
 835
 836 /* init the vis server. this may only be called when if_list is already
 837  * initialized (e.g. bat0 is initialized, interfaces have been added)
 838  */
 839 int batadv_vis_init(struct batadv_priv *bat_priv)
 840 {
 841         struct batadv_vis_packet *packet;
 842         int hash_added;
 843         unsigned int len;
 844         unsigned long first_seen;
 845         struct sk_buff *tmp_skb;
 846
 847         if (bat_priv->vis.hash)
 848                 return 0;
 849
 850         spin_lock_bh(&bat_priv->vis.hash_lock);
 851
 852         bat_priv->vis.hash = batadv_hash_new(256);
 853         if (!bat_priv->vis.hash) {
 854                 pr_err("Can't initialize vis_hash\n");
 855                 goto err;
 856         }
 857
 858         batadv_hash_set_lock_class(bat_priv->vis.hash,
 859                                    &batadv_vis_hash_lock_class_key);
 860
 861         bat_priv->vis.my_info = kmalloc(BATADV_MAX_VIS_PACKET_SIZE, GFP_ATOMIC);
 862         if (!bat_priv->vis.my_info)
 863                 goto err;
 864
 865         len = sizeof(*packet) + BATADV_MAX_VIS_PACKET_SIZE;
 866         len += ETH_HLEN + NET_IP_ALIGN;
 867         bat_priv->vis.my_info->skb_packet = dev_alloc_skb(len);
 868         if (!bat_priv->vis.my_info->skb_packet)
 869                 goto free_info;
 870
 871         skb_reserve(bat_priv->vis.my_info->skb_packet, ETH_HLEN + NET_IP_ALIGN);
 872         tmp_skb = bat_priv->vis.my_info->skb_packet;
 873         packet = (struct batadv_vis_packet *)skb_put(tmp_skb, sizeof(*packet));
 874
 875         /* prefill the vis info */
 876         first_seen = jiffies - msecs_to_jiffies(BATADV_VIS_INTERVAL);
 877         bat_priv->vis.my_info->first_seen = first_seen;
 878         INIT_LIST_HEAD(&bat_priv->vis.my_info->recv_list);
 879         INIT_LIST_HEAD(&bat_priv->vis.my_info->send_list);
 880         kref_init(&bat_priv->vis.my_info->refcount);
 881         bat_priv->vis.my_info->bat_priv = bat_priv;
 882         packet->header.version = BATADV_COMPAT_VERSION;
 883         packet->header.packet_type = BATADV_VIS;
 884         packet->header.ttl = BATADV_TTL;
 885         packet->seqno = 0;
 886         packet->reserved = 0;
 887         packet->entries = 0;
 888
 889         INIT_LIST_HEAD(&bat_priv->vis.send_list);
 890
 891         hash_added = batadv_hash_add(bat_priv->vis.hash, batadv_vis_info_cmp,
 892                                      batadv_vis_info_choose,
 893                                      bat_priv->vis.my_info,
 894                                      &bat_priv->vis.my_info->hash_entry);
 895         if (hash_added != 0) {
 896                 pr_err("Can't add own vis packet into hash\n");
 897                 /* not in hash, need to remove it manually. */
 898                 kref_put(&bat_priv->vis.my_info->refcount, batadv_free_info);
 899                 goto err;
 900         }
 901
 902         spin_unlock_bh(&bat_priv->vis.hash_lock);
 903         batadv_start_vis_timer(bat_priv);
 904         return 0;
 905
 906 free_info:
 907         kfree(bat_priv->vis.my_info);
 908         bat_priv->vis.my_info = NULL;
 909 err:
 910         spin_unlock_bh(&bat_priv->vis.hash_lock);
 911         batadv_vis_quit(bat_priv);
 912         return -ENOMEM;
 913 }
 914
 915 /* Decrease the reference count on a hash item info */
 916 static void batadv_free_info_ref(struct hlist_node *node, void *arg)
 917 {
 918         struct batadv_vis_info *info;
 919
 920         info = container_of(node, struct batadv_vis_info, hash_entry);
 921         batadv_send_list_del(info);
 922         kref_put(&info->refcount, batadv_free_info);
 923 }
 924
 925 /* shutdown vis-server */
 926 void batadv_vis_quit(struct batadv_priv *bat_priv)
 927 {
 928         if (!bat_priv->vis.hash)
 929                 return;
 930
 931         cancel_delayed_work_sync(&bat_priv->vis.work);
 932
 933         spin_lock_bh(&bat_priv->vis.hash_lock);
 934         /* properly remove, kill timers ... */
 935         batadv_hash_delete(bat_priv->vis.hash, batadv_free_info_ref, NULL);
 936         bat_priv->vis.hash = NULL;
 937         bat_priv->vis.my_info = NULL;
 938         spin_unlock_bh(&bat_priv->vis.hash_lock);
 939 }
 940
 941 /* schedule packets for (re)transmission */
 942 static void batadv_start_vis_timer(struct batadv_priv *bat_priv)
 943 {
 944         INIT_DELAYED_WORK(&bat_priv->vis.work, batadv_send_vis_packets);
 945         queue_delayed_work(batadv_event_workqueue, &bat_priv->vis.work,
 946                            msecs_to_jiffies(BATADV_VIS_INTERVAL));
 947 }