net/batman-adv/bat_iv_ogm.c

   1 /* Copyright (C) 2007-2013 B.A.T.M.A.N. contributors:
   2  *
   3  * Marek Lindner, 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 "translation-table.h"
  22 #include "originator.h"
  23 #include "routing.h"
  24 #include "gateway_common.h"
  25 #include "gateway_client.h"
  26 #include "hard-interface.h"
  27 #include "send.h"
  28 #include "bat_algo.h"
  29 #include "network-coding.h"
  30
  31 /**
  32  * batadv_ring_buffer_set - update the ring buffer with the given value
  33  * @lq_recv: pointer to the ring buffer
  34  * @lq_index: index to store the value at
  35  * @value: value to store in the ring buffer
  36  */
  37 static void batadv_ring_buffer_set(uint8_t lq_recv[], uint8_t *lq_index,
  38                                    uint8_t value)
  39 {
  40         lq_recv[*lq_index] = value;
  41         *lq_index = (*lq_index + 1) % BATADV_TQ_GLOBAL_WINDOW_SIZE;
  42 }
  43
  44 /**
  45  * batadv_ring_buffer_set - compute the average of all non-zero values stored
  46  * in the given ring buffer
  47  * @lq_recv: pointer to the ring buffer
  48  *
  49  * Returns computed average value.
  50  */
  51 static uint8_t batadv_ring_buffer_avg(const uint8_t lq_recv[])
  52 {
  53         const uint8_t *ptr;
  54         uint16_t count = 0, i = 0, sum = 0;
  55
  56         ptr = lq_recv;
  57
  58         while (i < BATADV_TQ_GLOBAL_WINDOW_SIZE) {
  59                 if (*ptr != 0) {
  60                         count++;
  61                         sum += *ptr;
  62                 }
  63
  64                 i++;
  65                 ptr++;
  66         }
  67
  68         if (count == 0)
  69                 return 0;
  70
  71         return (uint8_t)(sum / count);
  72 }
  73 static struct batadv_neigh_node *
  74 batadv_iv_ogm_neigh_new(struct batadv_hard_iface *hard_iface,
  75                         const uint8_t *neigh_addr,
  76                         struct batadv_orig_node *orig_node,
  77                         struct batadv_orig_node *orig_neigh)
  78 {
  79         struct batadv_neigh_node *neigh_node;
  80
  81         neigh_node = batadv_neigh_node_new(hard_iface, neigh_addr);
  82         if (!neigh_node)
  83                 goto out;
  84
  85         INIT_LIST_HEAD(&neigh_node->bonding_list);
  86
  87         neigh_node->orig_node = orig_neigh;
  88         neigh_node->if_incoming = hard_iface;
  89
  90         spin_lock_bh(&orig_node->neigh_list_lock);
  91         hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list);
  92         spin_unlock_bh(&orig_node->neigh_list_lock);
  93
  94 out:
  95         return neigh_node;
  96 }
  97
  98 static int batadv_iv_ogm_iface_enable(struct batadv_hard_iface *hard_iface)
  99 {
 100         struct batadv_ogm_packet *batadv_ogm_packet;
 101         unsigned char *ogm_buff;
 102         uint32_t random_seqno;
 103         int res = -ENOMEM;
 104
 105         /* randomize initial seqno to avoid collision */
 106         get_random_bytes(&random_seqno, sizeof(random_seqno));
 107         atomic_set(&hard_iface->bat_iv.ogm_seqno, random_seqno);
 108
 109         hard_iface->bat_iv.ogm_buff_len = BATADV_OGM_HLEN;
 110         ogm_buff = kmalloc(hard_iface->bat_iv.ogm_buff_len, GFP_ATOMIC);
 111         if (!ogm_buff)
 112                 goto out;
 113
 114         hard_iface->bat_iv.ogm_buff = ogm_buff;
 115
 116         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 117         batadv_ogm_packet->header.packet_type = BATADV_IV_OGM;
 118         batadv_ogm_packet->header.version = BATADV_COMPAT_VERSION;
 119         batadv_ogm_packet->header.ttl = 2;
 120         batadv_ogm_packet->flags = BATADV_NO_FLAGS;
 121         batadv_ogm_packet->tq = BATADV_TQ_MAX_VALUE;
 122         batadv_ogm_packet->tt_num_changes = 0;
 123         batadv_ogm_packet->ttvn = 0;
 124
 125         res = 0;
 126
 127 out:
 128         return res;
 129 }
 130
 131 static void batadv_iv_ogm_iface_disable(struct batadv_hard_iface *hard_iface)
 132 {
 133         kfree(hard_iface->bat_iv.ogm_buff);
 134         hard_iface->bat_iv.ogm_buff = NULL;
 135 }
 136
 137 static void batadv_iv_ogm_iface_update_mac(struct batadv_hard_iface *hard_iface)
 138 {
 139         struct batadv_ogm_packet *batadv_ogm_packet;
 140         unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
 141
 142         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 143         memcpy(batadv_ogm_packet->orig,
 144                hard_iface->net_dev->dev_addr, ETH_ALEN);
 145         memcpy(batadv_ogm_packet->prev_sender,
 146                hard_iface->net_dev->dev_addr, ETH_ALEN);
 147 }
 148
 149 static void
 150 batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface)
 151 {
 152         struct batadv_ogm_packet *batadv_ogm_packet;
 153         unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
 154
 155         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 156         batadv_ogm_packet->flags = BATADV_PRIMARIES_FIRST_HOP;
 157         batadv_ogm_packet->header.ttl = BATADV_TTL;
 158 }
 159
 160 /* when do we schedule our own ogm to be sent */
 161 static unsigned long
 162 batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
 163 {
 164         unsigned int msecs;
 165
 166         msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
 167         msecs += prandom_u32() % (2 * BATADV_JITTER);
 168
 169         return jiffies + msecs_to_jiffies(msecs);
 170 }
 171
 172 /* when do we schedule a ogm packet to be sent */
 173 static unsigned long batadv_iv_ogm_fwd_send_time(void)
 174 {
 175         return jiffies + msecs_to_jiffies(prandom_u32() % (BATADV_JITTER / 2));
 176 }
 177
 178 /* apply hop penalty for a normal link */
 179 static uint8_t batadv_hop_penalty(uint8_t tq,
 180                                   const struct batadv_priv *bat_priv)
 181 {
 182         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
 183         int new_tq;
 184
 185         new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty);
 186         new_tq /= BATADV_TQ_MAX_VALUE;
 187
 188         return new_tq;
 189 }
 190
 191 /* is there another aggregated packet here? */
 192 static int batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
 193                                      int tt_num_changes)
 194 {
 195         int next_buff_pos = 0;
 196
 197         next_buff_pos += buff_pos + BATADV_OGM_HLEN;
 198         next_buff_pos += batadv_tt_len(tt_num_changes);
 199
 200         return (next_buff_pos <= packet_len) &&
 201                (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
 202 }
 203
 204 /* send a batman ogm to a given interface */
 205 static void batadv_iv_ogm_send_to_if(struct batadv_forw_packet *forw_packet,
 206                                      struct batadv_hard_iface *hard_iface)
 207 {
 208         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 209         char *fwd_str;
 210         uint8_t packet_num;
 211         int16_t buff_pos;
 212         struct batadv_ogm_packet *batadv_ogm_packet;
 213         struct sk_buff *skb;
 214         uint8_t *packet_pos;
 215
 216         if (hard_iface->if_status != BATADV_IF_ACTIVE)
 217                 return;
 218
 219         packet_num = 0;
 220         buff_pos = 0;
 221         packet_pos = forw_packet->skb->data;
 222         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 223
 224         /* adjust all flags and log packets */
 225         while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
 226                                          batadv_ogm_packet->tt_num_changes)) {
 227                 /* we might have aggregated direct link packets with an
 228                  * ordinary base packet
 229                  */
 230                 if (forw_packet->direct_link_flags & BIT(packet_num) &&
 231                     forw_packet->if_incoming == hard_iface)
 232                         batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 233                 else
 234                         batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 235
 236                 if (packet_num > 0 || !forw_packet->own)
 237                         fwd_str = "Forwarding";
 238                 else
 239                         fwd_str = "Sending own";
 240
 241                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 242                            "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s, ttvn %d) on interface %s [%pM]\n",
 243                            fwd_str, (packet_num > 0 ? "aggregated " : ""),
 244                            batadv_ogm_packet->orig,
 245                            ntohl(batadv_ogm_packet->seqno),
 246                            batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl,
 247                            (batadv_ogm_packet->flags & BATADV_DIRECTLINK ?
 248                             "on" : "off"),
 249                            batadv_ogm_packet->ttvn, hard_iface->net_dev->name,
 250                            hard_iface->net_dev->dev_addr);
 251
 252                 buff_pos += BATADV_OGM_HLEN;
 253                 buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
 254                 packet_num++;
 255                 packet_pos = forw_packet->skb->data + buff_pos;
 256                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 257         }
 258
 259         /* create clone because function is called more than once */
 260         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
 261         if (skb) {
 262                 batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
 263                 batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
 264                                    skb->len + ETH_HLEN);
 265                 batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
 266         }
 267 }
 268
 269 /* send a batman ogm packet */
 270 static void batadv_iv_ogm_emit(struct batadv_forw_packet *forw_packet)
 271 {
 272         struct batadv_hard_iface *hard_iface;
 273         struct net_device *soft_iface;
 274         struct batadv_priv *bat_priv;
 275         struct batadv_hard_iface *primary_if = NULL;
 276         struct batadv_ogm_packet *batadv_ogm_packet;
 277         unsigned char directlink;
 278         uint8_t *packet_pos;
 279
 280         packet_pos = forw_packet->skb->data;
 281         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 282         directlink = (batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0);
 283
 284         if (!forw_packet->if_incoming) {
 285                 pr_err("Error - can't forward packet: incoming iface not specified\n");
 286                 goto out;
 287         }
 288
 289         soft_iface = forw_packet->if_incoming->soft_iface;
 290         bat_priv = netdev_priv(soft_iface);
 291
 292         if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE)
 293                 goto out;
 294
 295         primary_if = batadv_primary_if_get_selected(bat_priv);
 296         if (!primary_if)
 297                 goto out;
 298
 299         /* multihomed peer assumed
 300          * non-primary OGMs are only broadcasted on their interface
 301          */
 302         if ((directlink && (batadv_ogm_packet->header.ttl == 1)) ||
 303             (forw_packet->own && (forw_packet->if_incoming != primary_if))) {
 304                 /* FIXME: what about aggregated packets ? */
 305                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 306                            "%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n",
 307                            (forw_packet->own ? "Sending own" : "Forwarding"),
 308                            batadv_ogm_packet->orig,
 309                            ntohl(batadv_ogm_packet->seqno),
 310                            batadv_ogm_packet->header.ttl,
 311                            forw_packet->if_incoming->net_dev->name,
 312                            forw_packet->if_incoming->net_dev->dev_addr);
 313
 314                 /* skb is only used once and than forw_packet is free'd */
 315                 batadv_send_skb_packet(forw_packet->skb,
 316                                        forw_packet->if_incoming,
 317                                        batadv_broadcast_addr);
 318                 forw_packet->skb = NULL;
 319
 320                 goto out;
 321         }
 322
 323         /* broadcast on every interface */
 324         rcu_read_lock();
 325         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 326                 if (hard_iface->soft_iface != soft_iface)
 327                         continue;
 328
 329                 batadv_iv_ogm_send_to_if(forw_packet, hard_iface);
 330         }
 331         rcu_read_unlock();
 332
 333 out:
 334         if (primary_if)
 335                 batadv_hardif_free_ref(primary_if);
 336 }
 337
 338 /* return true if new_packet can be aggregated with forw_packet */
 339 static bool
 340 batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet,
 341                             struct batadv_priv *bat_priv,
 342                             int packet_len, unsigned long send_time,
 343                             bool directlink,
 344                             const struct batadv_hard_iface *if_incoming,
 345                             const struct batadv_forw_packet *forw_packet)
 346 {
 347         struct batadv_ogm_packet *batadv_ogm_packet;
 348         int aggregated_bytes = forw_packet->packet_len + packet_len;
 349         struct batadv_hard_iface *primary_if = NULL;
 350         bool res = false;
 351         unsigned long aggregation_end_time;
 352
 353         batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
 354         aggregation_end_time = send_time;
 355         aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 356
 357         /* we can aggregate the current packet to this aggregated packet
 358          * if:
 359          *
 360          * - the send time is within our MAX_AGGREGATION_MS time
 361          * - the resulting packet wont be bigger than
 362          *   MAX_AGGREGATION_BYTES
 363          */
 364         if (time_before(send_time, forw_packet->send_time) &&
 365             time_after_eq(aggregation_end_time, forw_packet->send_time) &&
 366             (aggregated_bytes <= BATADV_MAX_AGGREGATION_BYTES)) {
 367                 /* check aggregation compatibility
 368                  * -> direct link packets are broadcasted on
 369                  *    their interface only
 370                  * -> aggregate packet if the current packet is
 371                  *    a "global" packet as well as the base
 372                  *    packet
 373                  */
 374                 primary_if = batadv_primary_if_get_selected(bat_priv);
 375                 if (!primary_if)
 376                         goto out;
 377
 378                 /* packets without direct link flag and high TTL
 379                  * are flooded through the net
 380                  */
 381                 if ((!directlink) &&
 382                     (!(batadv_ogm_packet->flags & BATADV_DIRECTLINK)) &&
 383                     (batadv_ogm_packet->header.ttl != 1) &&
 384
 385                     /* own packets originating non-primary
 386                      * interfaces leave only that interface
 387                      */
 388                     ((!forw_packet->own) ||
 389                      (forw_packet->if_incoming == primary_if))) {
 390                         res = true;
 391                         goto out;
 392                 }
 393
 394                 /* if the incoming packet is sent via this one
 395                  * interface only - we still can aggregate
 396                  */
 397                 if ((directlink) &&
 398                     (new_bat_ogm_packet->header.ttl == 1) &&
 399                     (forw_packet->if_incoming == if_incoming) &&
 400
 401                     /* packets from direct neighbors or
 402                      * own secondary interface packets
 403                      * (= secondary interface packets in general)
 404                      */
 405                     (batadv_ogm_packet->flags & BATADV_DIRECTLINK ||
 406                      (forw_packet->own &&
 407                       forw_packet->if_incoming != primary_if))) {
 408                         res = true;
 409                         goto out;
 410                 }
 411         }
 412
 413 out:
 414         if (primary_if)
 415                 batadv_hardif_free_ref(primary_if);
 416         return res;
 417 }
 418
 419 /* create a new aggregated packet and add this packet to it */
 420 static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 421                                         int packet_len, unsigned long send_time,
 422                                         bool direct_link,
 423                                         struct batadv_hard_iface *if_incoming,
 424                                         int own_packet)
 425 {
 426         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 427         struct batadv_forw_packet *forw_packet_aggr;
 428         unsigned char *skb_buff;
 429         unsigned int skb_size;
 430
 431         if (!atomic_inc_not_zero(&if_incoming->refcount))
 432                 return;
 433
 434         /* own packet should always be scheduled */
 435         if (!own_packet) {
 436                 if (!batadv_atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
 437                         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 438                                    "batman packet queue full\n");
 439                         goto out;
 440                 }
 441         }
 442
 443         forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
 444         if (!forw_packet_aggr) {
 445                 if (!own_packet)
 446                         atomic_inc(&bat_priv->batman_queue_left);
 447                 goto out;
 448         }
 449
 450         if ((atomic_read(&bat_priv->aggregated_ogms)) &&
 451             (packet_len < BATADV_MAX_AGGREGATION_BYTES))
 452                 skb_size = BATADV_MAX_AGGREGATION_BYTES;
 453         else
 454                 skb_size = packet_len;
 455
 456         skb_size += ETH_HLEN;
 457
 458         forw_packet_aggr->skb = netdev_alloc_skb_ip_align(NULL, skb_size);
 459         if (!forw_packet_aggr->skb) {
 460                 if (!own_packet)
 461                         atomic_inc(&bat_priv->batman_queue_left);
 462                 kfree(forw_packet_aggr);
 463                 goto out;
 464         }
 465         skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
 466
 467         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 468         forw_packet_aggr->packet_len = packet_len;
 469         memcpy(skb_buff, packet_buff, packet_len);
 470
 471         forw_packet_aggr->own = own_packet;
 472         forw_packet_aggr->if_incoming = if_incoming;
 473         forw_packet_aggr->num_packets = 0;
 474         forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
 475         forw_packet_aggr->send_time = send_time;
 476
 477         /* save packet direct link flag status */
 478         if (direct_link)
 479                 forw_packet_aggr->direct_link_flags |= 1;
 480
 481         /* add new packet to packet list */
 482         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 483         hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
 484         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 485
 486         /* start timer for this packet */
 487         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 488                           batadv_send_outstanding_bat_ogm_packet);
 489         queue_delayed_work(batadv_event_workqueue,
 490                            &forw_packet_aggr->delayed_work,
 491                            send_time - jiffies);
 492
 493         return;
 494 out:
 495         batadv_hardif_free_ref(if_incoming);
 496 }
 497
 498 /* aggregate a new packet into the existing ogm packet */
 499 static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr,
 500                                     const unsigned char *packet_buff,
 501                                     int packet_len, bool direct_link)
 502 {
 503         unsigned char *skb_buff;
 504         unsigned long new_direct_link_flag;
 505
 506         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 507         memcpy(skb_buff, packet_buff, packet_len);
 508         forw_packet_aggr->packet_len += packet_len;
 509         forw_packet_aggr->num_packets++;
 510
 511         /* save packet direct link flag status */
 512         if (direct_link) {
 513                 new_direct_link_flag = BIT(forw_packet_aggr->num_packets);
 514                 forw_packet_aggr->direct_link_flags |= new_direct_link_flag;
 515         }
 516 }
 517
 518 static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv,
 519                                     unsigned char *packet_buff,
 520                                     int packet_len,
 521                                     struct batadv_hard_iface *if_incoming,
 522                                     int own_packet, unsigned long send_time)
 523 {
 524         /* _aggr -> pointer to the packet we want to aggregate with
 525          * _pos -> pointer to the position in the queue
 526          */
 527         struct batadv_forw_packet *forw_packet_aggr = NULL;
 528         struct batadv_forw_packet *forw_packet_pos = NULL;
 529         struct batadv_ogm_packet *batadv_ogm_packet;
 530         bool direct_link;
 531         unsigned long max_aggregation_jiffies;
 532
 533         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
 534         direct_link = batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0;
 535         max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 536
 537         /* find position for the packet in the forward queue */
 538         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 539         /* own packets are not to be aggregated */
 540         if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
 541                 hlist_for_each_entry(forw_packet_pos,
 542                                      &bat_priv->forw_bat_list, list) {
 543                         if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet,
 544                                                         bat_priv, packet_len,
 545                                                         send_time, direct_link,
 546                                                         if_incoming,
 547                                                         forw_packet_pos)) {
 548                                 forw_packet_aggr = forw_packet_pos;
 549                                 break;
 550                         }
 551                 }
 552         }
 553
 554         /* nothing to aggregate with - either aggregation disabled or no
 555          * suitable aggregation packet found
 556          */
 557         if (!forw_packet_aggr) {
 558                 /* the following section can run without the lock */
 559                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 560
 561                 /* if we could not aggregate this packet with one of the others
 562                  * we hold it back for a while, so that it might be aggregated
 563                  * later on
 564                  */
 565                 if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
 566                         send_time += max_aggregation_jiffies;
 567
 568                 batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
 569                                             send_time, direct_link,
 570                                             if_incoming, own_packet);
 571         } else {
 572                 batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 573                                         packet_len, direct_link);
 574                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 575         }
 576 }
 577
 578 static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
 579                                   const struct ethhdr *ethhdr,
 580                                   struct batadv_ogm_packet *batadv_ogm_packet,
 581                                   bool is_single_hop_neigh,
 582                                   bool is_from_best_next_hop,
 583                                   struct batadv_hard_iface *if_incoming)
 584 {
 585         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 586         uint8_t tt_num_changes;
 587
 588         if (batadv_ogm_packet->header.ttl <= 1) {
 589                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
 590                 return;
 591         }
 592
 593         if (!is_from_best_next_hop) {
 594                 /* Mark the forwarded packet when it is not coming from our
 595                  * best next hop. We still need to forward the packet for our
 596                  * neighbor link quality detection to work in case the packet
 597                  * originated from a single hop neighbor. Otherwise we can
 598                  * simply drop the ogm.
 599                  */
 600                 if (is_single_hop_neigh)
 601                         batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP;
 602                 else
 603                         return;
 604         }
 605
 606         tt_num_changes = batadv_ogm_packet->tt_num_changes;
 607
 608         batadv_ogm_packet->header.ttl--;
 609         memcpy(batadv_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 610
 611         /* apply hop penalty */
 612         batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq,
 613                                                    bat_priv);
 614
 615         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 616                    "Forwarding packet: tq: %i, ttl: %i\n",
 617                    batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl);
 618
 619         /* switch of primaries first hop flag when forwarding */
 620         batadv_ogm_packet->flags &= ~BATADV_PRIMARIES_FIRST_HOP;
 621         if (is_single_hop_neigh)
 622                 batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 623         else
 624                 batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 625
 626         batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
 627                                 BATADV_OGM_HLEN + batadv_tt_len(tt_num_changes),
 628                                 if_incoming, 0, batadv_iv_ogm_fwd_send_time());
 629 }
 630
 631 /**
 632  * batadv_iv_ogm_slide_own_bcast_window - bitshift own OGM broadcast windows for
 633  * the given interface
 634  * @hard_iface: the interface for which the windows have to be shifted
 635  */
 636 static void
 637 batadv_iv_ogm_slide_own_bcast_window(struct batadv_hard_iface *hard_iface)
 638 {
 639         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 640         struct batadv_hashtable *hash = bat_priv->orig_hash;
 641         struct hlist_head *head;
 642         struct batadv_orig_node *orig_node;
 643         unsigned long *word;
 644         uint32_t i;
 645         size_t word_index;
 646         uint8_t *w;
 647
 648         for (i = 0; i < hash->size; i++) {
 649                 head = &hash->table[i];
 650
 651                 rcu_read_lock();
 652                 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
 653                         spin_lock_bh(&orig_node->ogm_cnt_lock);
 654                         word_index = hard_iface->if_num * BATADV_NUM_WORDS;
 655                         word = &(orig_node->bcast_own[word_index]);
 656
 657                         batadv_bit_get_packet(bat_priv, word, 1, 0);
 658                         w = &orig_node->bcast_own_sum[hard_iface->if_num];
 659                         *w = bitmap_weight(word, BATADV_TQ_LOCAL_WINDOW_SIZE);
 660                         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 661                 }
 662                 rcu_read_unlock();
 663         }
 664 }
 665
 666 static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
 667 {
 668         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 669         unsigned char **ogm_buff = &hard_iface->bat_iv.ogm_buff;
 670         struct batadv_ogm_packet *batadv_ogm_packet;
 671         struct batadv_hard_iface *primary_if;
 672         int *ogm_buff_len = &hard_iface->bat_iv.ogm_buff_len;
 673         int vis_server, tt_num_changes = 0;
 674         uint32_t seqno;
 675         uint8_t bandwidth;
 676
 677         vis_server = atomic_read(&bat_priv->vis_mode);
 678         primary_if = batadv_primary_if_get_selected(bat_priv);
 679
 680         if (hard_iface == primary_if)
 681                 tt_num_changes = batadv_tt_append_diff(bat_priv, ogm_buff,
 682                                                        ogm_buff_len,
 683                                                        BATADV_OGM_HLEN);
 684
 685         batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff);
 686
 687         /* change sequence number to network order */
 688         seqno = (uint32_t)atomic_read(&hard_iface->bat_iv.ogm_seqno);
 689         batadv_ogm_packet->seqno = htonl(seqno);
 690         atomic_inc(&hard_iface->bat_iv.ogm_seqno);
 691
 692         batadv_ogm_packet->ttvn = atomic_read(&bat_priv->tt.vn);
 693         batadv_ogm_packet->tt_crc = htons(bat_priv->tt.local_crc);
 694         if (tt_num_changes >= 0)
 695                 batadv_ogm_packet->tt_num_changes = tt_num_changes;
 696
 697         if (vis_server == BATADV_VIS_TYPE_SERVER_SYNC)
 698                 batadv_ogm_packet->flags |= BATADV_VIS_SERVER;
 699         else
 700                 batadv_ogm_packet->flags &= ~BATADV_VIS_SERVER;
 701
 702         if (hard_iface == primary_if &&
 703             atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_SERVER) {
 704                 bandwidth = (uint8_t)atomic_read(&bat_priv->gw_bandwidth);
 705                 batadv_ogm_packet->gw_flags = bandwidth;
 706         } else {
 707                 batadv_ogm_packet->gw_flags = BATADV_NO_FLAGS;
 708         }
 709
 710         batadv_iv_ogm_slide_own_bcast_window(hard_iface);
 711         batadv_iv_ogm_queue_add(bat_priv, hard_iface->bat_iv.ogm_buff,
 712                                 hard_iface->bat_iv.ogm_buff_len, hard_iface, 1,
 713                                 batadv_iv_ogm_emit_send_time(bat_priv));
 714
 715         if (primary_if)
 716                 batadv_hardif_free_ref(primary_if);
 717 }
 718
 719 static void
 720 batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv,
 721                           struct batadv_orig_node *orig_node,
 722                           const struct ethhdr *ethhdr,
 723                           const struct batadv_ogm_packet *batadv_ogm_packet,
 724                           struct batadv_hard_iface *if_incoming,
 725                           const unsigned char *tt_buff,
 726                           int is_duplicate)
 727 {
 728         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 729         struct batadv_neigh_node *router = NULL;
 730         struct batadv_orig_node *orig_node_tmp;
 731         int if_num;
 732         uint8_t sum_orig, sum_neigh;
 733         uint8_t *neigh_addr;
 734         uint8_t tq_avg;
 735
 736         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 737                    "update_originator(): Searching and updating originator entry of received packet\n");
 738
 739         rcu_read_lock();
 740         hlist_for_each_entry_rcu(tmp_neigh_node,
 741                                  &orig_node->neigh_list, list) {
 742                 neigh_addr = tmp_neigh_node->addr;
 743                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 744                     tmp_neigh_node->if_incoming == if_incoming &&
 745                     atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
 746                         if (WARN(neigh_node, "too many matching neigh_nodes"))
 747                                 batadv_neigh_node_free_ref(neigh_node);
 748                         neigh_node = tmp_neigh_node;
 749                         continue;
 750                 }
 751
 752                 if (is_duplicate)
 753                         continue;
 754
 755                 spin_lock_bh(&tmp_neigh_node->lq_update_lock);
 756                 batadv_ring_buffer_set(tmp_neigh_node->tq_recv,
 757                                        &tmp_neigh_node->tq_index, 0);
 758                 tq_avg = batadv_ring_buffer_avg(tmp_neigh_node->tq_recv);
 759                 tmp_neigh_node->tq_avg = tq_avg;
 760                 spin_unlock_bh(&tmp_neigh_node->lq_update_lock);
 761         }
 762
 763         if (!neigh_node) {
 764                 struct batadv_orig_node *orig_tmp;
 765
 766                 orig_tmp = batadv_get_orig_node(bat_priv, ethhdr->h_source);
 767                 if (!orig_tmp)
 768                         goto unlock;
 769
 770                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 771                                                      ethhdr->h_source,
 772                                                      orig_node, orig_tmp);
 773
 774                 batadv_orig_node_free_ref(orig_tmp);
 775                 if (!neigh_node)
 776                         goto unlock;
 777         } else
 778                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 779                            "Updating existing last-hop neighbor of originator\n");
 780
 781         rcu_read_unlock();
 782
 783         orig_node->flags = batadv_ogm_packet->flags;
 784         neigh_node->last_seen = jiffies;
 785
 786         spin_lock_bh(&neigh_node->lq_update_lock);
 787         batadv_ring_buffer_set(neigh_node->tq_recv,
 788                                &neigh_node->tq_index,
 789                                batadv_ogm_packet->tq);
 790         neigh_node->tq_avg = batadv_ring_buffer_avg(neigh_node->tq_recv);
 791         spin_unlock_bh(&neigh_node->lq_update_lock);
 792
 793         if (!is_duplicate) {
 794                 orig_node->last_ttl = batadv_ogm_packet->header.ttl;
 795                 neigh_node->last_ttl = batadv_ogm_packet->header.ttl;
 796         }
 797
 798         batadv_bonding_candidate_add(orig_node, neigh_node);
 799
 800         /* if this neighbor already is our next hop there is nothing
 801          * to change
 802          */
 803         router = batadv_orig_node_get_router(orig_node);
 804         if (router == neigh_node)
 805                 goto update_tt;
 806
 807         /* if this neighbor does not offer a better TQ we won't consider it */
 808         if (router && (router->tq_avg > neigh_node->tq_avg))
 809                 goto update_tt;
 810
 811         /* if the TQ is the same and the link not more symmetric we
 812          * won't consider it either
 813          */
 814         if (router && (neigh_node->tq_avg == router->tq_avg)) {
 815                 orig_node_tmp = router->orig_node;
 816                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 817                 if_num = router->if_incoming->if_num;
 818                 sum_orig = orig_node_tmp->bcast_own_sum[if_num];
 819                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 820
 821                 orig_node_tmp = neigh_node->orig_node;
 822                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 823                 if_num = neigh_node->if_incoming->if_num;
 824                 sum_neigh = orig_node_tmp->bcast_own_sum[if_num];
 825                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 826
 827                 if (sum_orig >= sum_neigh)
 828                         goto update_tt;
 829         }
 830
 831         batadv_update_route(bat_priv, orig_node, neigh_node);
 832
 833 update_tt:
 834         /* I have to check for transtable changes only if the OGM has been
 835          * sent through a primary interface
 836          */
 837         if (((batadv_ogm_packet->orig != ethhdr->h_source) &&
 838              (batadv_ogm_packet->header.ttl > 2)) ||
 839             (batadv_ogm_packet->flags & BATADV_PRIMARIES_FIRST_HOP))
 840                 batadv_tt_update_orig(bat_priv, orig_node, tt_buff,
 841                                       batadv_ogm_packet->tt_num_changes,
 842                                       batadv_ogm_packet->ttvn,
 843                                       ntohs(batadv_ogm_packet->tt_crc));
 844
 845         if (orig_node->gw_flags != batadv_ogm_packet->gw_flags)
 846                 batadv_gw_node_update(bat_priv, orig_node,
 847                                       batadv_ogm_packet->gw_flags);
 848
 849         orig_node->gw_flags = batadv_ogm_packet->gw_flags;
 850
 851         /* restart gateway selection if fast or late switching was enabled */
 852         if ((orig_node->gw_flags) &&
 853             (atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_CLIENT) &&
 854             (atomic_read(&bat_priv->gw_sel_class) > 2))
 855                 batadv_gw_check_election(bat_priv, orig_node);
 856
 857         goto out;
 858
 859 unlock:
 860         rcu_read_unlock();
 861 out:
 862         if (neigh_node)
 863                 batadv_neigh_node_free_ref(neigh_node);
 864         if (router)
 865                 batadv_neigh_node_free_ref(router);
 866 }
 867
 868 static int batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
 869                                  struct batadv_orig_node *orig_neigh_node,
 870                                  struct batadv_ogm_packet *batadv_ogm_packet,
 871                                  struct batadv_hard_iface *if_incoming)
 872 {
 873         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 874         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node;
 875         uint8_t total_count;
 876         uint8_t orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
 877         unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
 878         int tq_asym_penalty, inv_asym_penalty, ret = 0;
 879         unsigned int combined_tq;
 880
 881         /* find corresponding one hop neighbor */
 882         rcu_read_lock();
 883         hlist_for_each_entry_rcu(tmp_neigh_node,
 884                                  &orig_neigh_node->neigh_list, list) {
 885                 if (!batadv_compare_eth(tmp_neigh_node->addr,
 886                                         orig_neigh_node->orig))
 887                         continue;
 888
 889                 if (tmp_neigh_node->if_incoming != if_incoming)
 890                         continue;
 891
 892                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 893                         continue;
 894
 895                 neigh_node = tmp_neigh_node;
 896                 break;
 897         }
 898         rcu_read_unlock();
 899
 900         if (!neigh_node)
 901                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 902                                                      orig_neigh_node->orig,
 903                                                      orig_neigh_node,
 904                                                      orig_neigh_node);
 905
 906         if (!neigh_node)
 907                 goto out;
 908
 909         /* if orig_node is direct neighbor update neigh_node last_seen */
 910         if (orig_node == orig_neigh_node)
 911                 neigh_node->last_seen = jiffies;
 912
 913         orig_node->last_seen = jiffies;
 914
 915         /* find packet count of corresponding one hop neighbor */
 916         spin_lock_bh(&orig_node->ogm_cnt_lock);
 917         orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
 918         neigh_rq_count = neigh_node->real_packet_count;
 919         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 920
 921         /* pay attention to not get a value bigger than 100 % */
 922         if (orig_eq_count > neigh_rq_count)
 923                 total_count = neigh_rq_count;
 924         else
 925                 total_count = orig_eq_count;
 926
 927         /* if we have too few packets (too less data) we set tq_own to zero
 928          * if we receive too few packets it is not considered bidirectional
 929          */
 930         if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
 931             neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
 932                 tq_own = 0;
 933         else
 934                 /* neigh_node->real_packet_count is never zero as we
 935                  * only purge old information when getting new
 936                  * information
 937                  */
 938                 tq_own = (BATADV_TQ_MAX_VALUE * total_count) /  neigh_rq_count;
 939
 940         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 941          * affect the nearly-symmetric links only a little, but
 942          * punishes asymmetric links more.  This will give a value
 943          * between 0 and TQ_MAX_VALUE
 944          */
 945         neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
 946         neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
 947         neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
 948                             BATADV_TQ_LOCAL_WINDOW_SIZE *
 949                             BATADV_TQ_LOCAL_WINDOW_SIZE;
 950         inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
 951         inv_asym_penalty /= neigh_rq_max_cube;
 952         tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;
 953
 954         combined_tq = batadv_ogm_packet->tq * tq_own * tq_asym_penalty;
 955         combined_tq /= BATADV_TQ_MAX_VALUE * BATADV_TQ_MAX_VALUE;
 956         batadv_ogm_packet->tq = combined_tq;
 957
 958         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 959                    "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n",
 960                    orig_node->orig, orig_neigh_node->orig, total_count,
 961                    neigh_rq_count, tq_own,
 962                    tq_asym_penalty, batadv_ogm_packet->tq);
 963
 964         /* if link has the minimum required transmission quality
 965          * consider it bidirectional
 966          */
 967         if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
 968                 ret = 1;
 969
 970 out:
 971         if (neigh_node)
 972                 batadv_neigh_node_free_ref(neigh_node);
 973         return ret;
 974 }
 975
 976 /* processes a batman packet for all interfaces, adjusts the sequence number and
 977  * finds out whether it is a duplicate.
 978  * returns:
 979  *   1 the packet is a duplicate
 980  *   0 the packet has not yet been received
 981  *  -1 the packet is old and has been received while the seqno window
 982  *     was protected. Caller should drop it.
 983  */
 984 static int
 985 batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
 986                             const struct batadv_ogm_packet *batadv_ogm_packet,
 987                             const struct batadv_hard_iface *if_incoming)
 988 {
 989         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 990         struct batadv_orig_node *orig_node;
 991         struct batadv_neigh_node *tmp_neigh_node;
 992         int is_duplicate = 0;
 993         int32_t seq_diff;
 994         int need_update = 0;
 995         int set_mark, ret = -1;
 996         uint32_t seqno = ntohl(batadv_ogm_packet->seqno);
 997         uint8_t *neigh_addr;
 998         uint8_t packet_count;
 999
1000         orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig);
1001         if (!orig_node)
1002                 return 0;
1003
1004         spin_lock_bh(&orig_node->ogm_cnt_lock);
1005         seq_diff = seqno - orig_node->last_real_seqno;
1006
1007         /* signalize caller that the packet is to be dropped. */
1008         if (!hlist_empty(&orig_node->neigh_list) &&
1009             batadv_window_protected(bat_priv, seq_diff,
1010                                     &orig_node->batman_seqno_reset))
1011                 goto out;
1012
1013         rcu_read_lock();
1014         hlist_for_each_entry_rcu(tmp_neigh_node,
1015                                  &orig_node->neigh_list, list) {
1016                 is_duplicate |= batadv_test_bit(tmp_neigh_node->real_bits,
1017                                                 orig_node->last_real_seqno,
1018                                                 seqno);
1019
1020                 neigh_addr = tmp_neigh_node->addr;
1021                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
1022                     tmp_neigh_node->if_incoming == if_incoming)
1023                         set_mark = 1;
1024                 else
1025                         set_mark = 0;
1026
1027                 /* if the window moved, set the update flag. */
1028                 need_update |= batadv_bit_get_packet(bat_priv,
1029                                                      tmp_neigh_node->real_bits,
1030                                                      seq_diff, set_mark);
1031
1032                 packet_count = bitmap_weight(tmp_neigh_node->real_bits,
1033                                              BATADV_TQ_LOCAL_WINDOW_SIZE);
1034                 tmp_neigh_node->real_packet_count = packet_count;
1035         }
1036         rcu_read_unlock();
1037
1038         if (need_update) {
1039                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1040                            "updating last_seqno: old %u, new %u\n",
1041                            orig_node->last_real_seqno, seqno);
1042                 orig_node->last_real_seqno = seqno;
1043         }
1044
1045         ret = is_duplicate;
1046
1047 out:
1048         spin_unlock_bh(&orig_node->ogm_cnt_lock);
1049         batadv_orig_node_free_ref(orig_node);
1050         return ret;
1051 }
1052
1053 static void batadv_iv_ogm_process(const struct ethhdr *ethhdr,
1054                                   struct batadv_ogm_packet *batadv_ogm_packet,
1055                                   const unsigned char *tt_buff,
1056                                   struct batadv_hard_iface *if_incoming)
1057 {
1058         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1059         struct batadv_hard_iface *hard_iface;
1060         struct batadv_orig_node *orig_neigh_node, *orig_node;
1061         struct batadv_neigh_node *router = NULL, *router_router = NULL;
1062         struct batadv_neigh_node *orig_neigh_router = NULL;
1063         int has_directlink_flag;
1064         int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
1065         int is_bidirect;
1066         bool is_single_hop_neigh = false;
1067         bool is_from_best_next_hop = false;
1068         int is_duplicate, sameseq, simlar_ttl;
1069         uint32_t if_incoming_seqno;
1070         uint8_t *prev_sender;
1071
1072         /* Silently drop when the batman packet is actually not a
1073          * correct packet.
1074          *
1075          * This might happen if a packet is padded (e.g. Ethernet has a
1076          * minimum frame length of 64 byte) and the aggregation interprets
1077          * it as an additional length.
1078          *
1079          * TODO: A more sane solution would be to have a bit in the
1080          * batadv_ogm_packet to detect whether the packet is the last
1081          * packet in an aggregation.  Here we expect that the padding
1082          * is always zero (or not 0x01)
1083          */
1084         if (batadv_ogm_packet->header.packet_type != BATADV_IV_OGM)
1085                 return;
1086
1087         /* could be changed by schedule_own_packet() */
1088         if_incoming_seqno = atomic_read(&if_incoming->bat_iv.ogm_seqno);
1089
1090         if (batadv_ogm_packet->flags & BATADV_DIRECTLINK)
1091                 has_directlink_flag = 1;
1092         else
1093                 has_directlink_flag = 0;
1094
1095         if (batadv_compare_eth(ethhdr->h_source, batadv_ogm_packet->orig))
1096                 is_single_hop_neigh = true;
1097
1098         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1099                    "Received BATMAN packet via NB: %pM, IF: %s [%pM] (from OG: %pM, via prev OG: %pM, seqno %u, ttvn %u, crc %#.4x, changes %u, tq %d, TTL %d, V %d, IDF %d)\n",
1100                    ethhdr->h_source, if_incoming->net_dev->name,
1101                    if_incoming->net_dev->dev_addr, batadv_ogm_packet->orig,
1102                    batadv_ogm_packet->prev_sender,
1103                    ntohl(batadv_ogm_packet->seqno), batadv_ogm_packet->ttvn,
1104                    ntohs(batadv_ogm_packet->tt_crc),
1105                    batadv_ogm_packet->tt_num_changes, batadv_ogm_packet->tq,
1106                    batadv_ogm_packet->header.ttl,
1107                    batadv_ogm_packet->header.version, has_directlink_flag);
1108
1109         rcu_read_lock();
1110         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1111                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
1112                         continue;
1113
1114                 if (hard_iface->soft_iface != if_incoming->soft_iface)
1115                         continue;
1116
1117                 if (batadv_compare_eth(ethhdr->h_source,
1118                                        hard_iface->net_dev->dev_addr))
1119                         is_my_addr = 1;
1120
1121                 if (batadv_compare_eth(batadv_ogm_packet->orig,
1122                                        hard_iface->net_dev->dev_addr))
1123                         is_my_orig = 1;
1124
1125                 if (batadv_compare_eth(batadv_ogm_packet->prev_sender,
1126                                        hard_iface->net_dev->dev_addr))
1127                         is_my_oldorig = 1;
1128         }
1129         rcu_read_unlock();
1130
1131         if (is_my_addr) {
1132                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1133                            "Drop packet: received my own broadcast (sender: %pM)\n",
1134                            ethhdr->h_source);
1135                 return;
1136         }
1137
1138         if (is_my_orig) {
1139                 unsigned long *word;
1140                 int offset;
1141                 int32_t bit_pos;
1142                 int16_t if_num;
1143                 uint8_t *weight;
1144
1145                 orig_neigh_node = batadv_get_orig_node(bat_priv,
1146                                                        ethhdr->h_source);
1147                 if (!orig_neigh_node)
1148                         return;
1149
1150                 /* neighbor has to indicate direct link and it has to
1151                  * come via the corresponding interface
1152                  * save packet seqno for bidirectional check
1153                  */
1154                 if (has_directlink_flag &&
1155                     batadv_compare_eth(if_incoming->net_dev->dev_addr,
1156                                        batadv_ogm_packet->orig)) {
1157                         if_num = if_incoming->if_num;
1158                         offset = if_num * BATADV_NUM_WORDS;
1159
1160                         spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
1161                         word = &(orig_neigh_node->bcast_own[offset]);
1162                         bit_pos = if_incoming_seqno - 2;
1163                         bit_pos -= ntohl(batadv_ogm_packet->seqno);
1164                         batadv_set_bit(word, bit_pos);
1165                         weight = &orig_neigh_node->bcast_own_sum[if_num];
1166                         *weight = bitmap_weight(word,
1167                                                 BATADV_TQ_LOCAL_WINDOW_SIZE);
1168                         spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
1169                 }
1170
1171                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1172                            "Drop packet: originator packet from myself (via neighbor)\n");
1173                 batadv_orig_node_free_ref(orig_neigh_node);
1174                 return;
1175         }
1176
1177         if (is_my_oldorig) {
1178                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1179                            "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1180                            ethhdr->h_source);
1181                 return;
1182         }
1183
1184         if (batadv_ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) {
1185                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1186                            "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1187                            ethhdr->h_source);
1188                 return;
1189         }
1190
1191         orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig);
1192         if (!orig_node)
1193                 return;
1194
1195         is_duplicate = batadv_iv_ogm_update_seqnos(ethhdr, batadv_ogm_packet,
1196                                                    if_incoming);
1197
1198         if (is_duplicate == -1) {
1199                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1200                            "Drop packet: packet within seqno protection time (sender: %pM)\n",
1201                            ethhdr->h_source);
1202                 goto out;
1203         }
1204
1205         if (batadv_ogm_packet->tq == 0) {
1206                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1207                            "Drop packet: originator packet with tq equal 0\n");
1208                 goto out;
1209         }
1210
1211         router = batadv_orig_node_get_router(orig_node);
1212         if (router)
1213                 router_router = batadv_orig_node_get_router(router->orig_node);
1214
1215         if ((router && router->tq_avg != 0) &&
1216             (batadv_compare_eth(router->addr, ethhdr->h_source)))
1217                 is_from_best_next_hop = true;
1218
1219         prev_sender = batadv_ogm_packet->prev_sender;
1220         /* avoid temporary routing loops */
1221         if (router && router_router &&
1222             (batadv_compare_eth(router->addr, prev_sender)) &&
1223             !(batadv_compare_eth(batadv_ogm_packet->orig, prev_sender)) &&
1224             (batadv_compare_eth(router->addr, router_router->addr))) {
1225                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1226                            "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1227                            ethhdr->h_source);
1228                 goto out;
1229         }
1230
1231         /* if sender is a direct neighbor the sender mac equals
1232          * originator mac
1233          */
1234         if (is_single_hop_neigh)
1235                 orig_neigh_node = orig_node;
1236         else
1237                 orig_neigh_node = batadv_get_orig_node(bat_priv,
1238                                                        ethhdr->h_source);
1239
1240         if (!orig_neigh_node)
1241                 goto out;
1242
1243         /* Update nc_nodes of the originator */
1244         batadv_nc_update_nc_node(bat_priv, orig_node, orig_neigh_node,
1245                                  batadv_ogm_packet, is_single_hop_neigh);
1246
1247         orig_neigh_router = batadv_orig_node_get_router(orig_neigh_node);
1248
1249         /* drop packet if sender is not a direct neighbor and if we
1250          * don't route towards it
1251          */
1252         if (!is_single_hop_neigh && (!orig_neigh_router)) {
1253                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1254                            "Drop packet: OGM via unknown neighbor!\n");
1255                 goto out_neigh;
1256         }
1257
1258         is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1259                                             batadv_ogm_packet, if_incoming);
1260
1261         batadv_bonding_save_primary(orig_node, orig_neigh_node,
1262                                     batadv_ogm_packet);
1263
1264         /* update ranking if it is not a duplicate or has the same
1265          * seqno and similar ttl as the non-duplicate
1266          */
1267         sameseq = orig_node->last_real_seqno == ntohl(batadv_ogm_packet->seqno);
1268         simlar_ttl = orig_node->last_ttl - 3 <= batadv_ogm_packet->header.ttl;
1269         if (is_bidirect && (!is_duplicate || (sameseq && simlar_ttl)))
1270                 batadv_iv_ogm_orig_update(bat_priv, orig_node, ethhdr,
1271                                           batadv_ogm_packet, if_incoming,
1272                                           tt_buff, is_duplicate);
1273
1274         /* is single hop (direct) neighbor */
1275         if (is_single_hop_neigh) {
1276                 /* mark direct link on incoming interface */
1277                 batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1278                                       is_single_hop_neigh,
1279                                       is_from_best_next_hop, if_incoming);
1280
1281                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1282                            "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1283                 goto out_neigh;
1284         }
1285
1286         /* multihop originator */
1287         if (!is_bidirect) {
1288                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1289                            "Drop packet: not received via bidirectional link\n");
1290                 goto out_neigh;
1291         }
1292
1293         if (is_duplicate) {
1294                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1295                            "Drop packet: duplicate packet received\n");
1296                 goto out_neigh;
1297         }
1298
1299         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1300                    "Forwarding packet: rebroadcast originator packet\n");
1301         batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1302                               is_single_hop_neigh, is_from_best_next_hop,
1303                               if_incoming);
1304
1305 out_neigh:
1306         if ((orig_neigh_node) && (!is_single_hop_neigh))
1307                 batadv_orig_node_free_ref(orig_neigh_node);
1308 out:
1309         if (router)
1310                 batadv_neigh_node_free_ref(router);
1311         if (router_router)
1312                 batadv_neigh_node_free_ref(router_router);
1313         if (orig_neigh_router)
1314                 batadv_neigh_node_free_ref(orig_neigh_router);
1315
1316         batadv_orig_node_free_ref(orig_node);
1317 }
1318
1319 static int batadv_iv_ogm_receive(struct sk_buff *skb,
1320                                  struct batadv_hard_iface *if_incoming)
1321 {
1322         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1323         struct batadv_ogm_packet *batadv_ogm_packet;
1324         struct ethhdr *ethhdr;
1325         int buff_pos = 0, packet_len;
1326         unsigned char *tt_buff, *packet_buff;
1327         bool ret;
1328         uint8_t *packet_pos;
1329
1330         ret = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
1331         if (!ret)
1332                 return NET_RX_DROP;
1333
1334         /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1335          * that does not have B.A.T.M.A.N. IV enabled ?
1336          */
1337         if (bat_priv->bat_algo_ops->bat_ogm_emit != batadv_iv_ogm_emit)
1338                 return NET_RX_DROP;
1339
1340         batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
1341         batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
1342                            skb->len + ETH_HLEN);
1343
1344         packet_len = skb_headlen(skb);
1345         ethhdr = eth_hdr(skb);
1346         packet_buff = skb->data;
1347         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
1348
1349         /* unpack the aggregated packets and process them one by one */
1350         while (batadv_iv_ogm_aggr_packet(buff_pos, packet_len,
1351                                          batadv_ogm_packet->tt_num_changes)) {
1352                 tt_buff = packet_buff + buff_pos + BATADV_OGM_HLEN;
1353
1354                 batadv_iv_ogm_process(ethhdr, batadv_ogm_packet, tt_buff,
1355                                       if_incoming);
1356
1357                 buff_pos += BATADV_OGM_HLEN;
1358                 buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
1359
1360                 packet_pos = packet_buff + buff_pos;
1361                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
1362         }
1363
1364         kfree_skb(skb);
1365         return NET_RX_SUCCESS;
1366 }
1367
1368 static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
1369         .name = "BATMAN_IV",
1370         .bat_iface_enable = batadv_iv_ogm_iface_enable,
1371         .bat_iface_disable = batadv_iv_ogm_iface_disable,
1372         .bat_iface_update_mac = batadv_iv_ogm_iface_update_mac,
1373         .bat_primary_iface_set = batadv_iv_ogm_primary_iface_set,
1374         .bat_ogm_schedule = batadv_iv_ogm_schedule,
1375         .bat_ogm_emit = batadv_iv_ogm_emit,
1376 };
1377
1378 int __init batadv_iv_init(void)
1379 {
1380         int ret;
1381
1382         /* batman originator packet */
1383         ret = batadv_recv_handler_register(BATADV_IV_OGM,
1384                                            batadv_iv_ogm_receive);
1385         if (ret < 0)
1386                 goto out;
1387
1388         ret = batadv_algo_register(&batadv_batman_iv);
1389         if (ret < 0)
1390                 goto handler_unregister;
1391
1392         goto out;
1393
1394 handler_unregister:
1395         batadv_recv_handler_unregister(BATADV_IV_OGM);
1396 out:
1397         return ret;
1398 }