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 /**
  33  * batadv_dup_status - duplicate status
  34  * @BATADV_NO_DUP: the packet is a duplicate
  35  * @BATADV_ORIG_DUP: OGM is a duplicate in the originator (but not for the
  36  *  neighbor)
  37  * @BATADV_NEIGH_DUP: OGM is a duplicate for the neighbor
  38  * @BATADV_PROTECTED: originator is currently protected (after reboot)
  39  */
  40 enum batadv_dup_status {
  41         BATADV_NO_DUP = 0,
  42         BATADV_ORIG_DUP,
  43         BATADV_NEIGH_DUP,
  44         BATADV_PROTECTED,
  45 };
  46
  47 /**
  48  * batadv_ring_buffer_set - update the ring buffer with the given value
  49  * @lq_recv: pointer to the ring buffer
  50  * @lq_index: index to store the value at
  51  * @value: value to store in the ring buffer
  52  */
  53 static void batadv_ring_buffer_set(uint8_t lq_recv[], uint8_t *lq_index,
  54                                    uint8_t value)
  55 {
  56         lq_recv[*lq_index] = value;
  57         *lq_index = (*lq_index + 1) % BATADV_TQ_GLOBAL_WINDOW_SIZE;
  58 }
  59
  60 /**
  61  * batadv_ring_buffer_set - compute the average of all non-zero values stored
  62  * in the given ring buffer
  63  * @lq_recv: pointer to the ring buffer
  64  *
  65  * Returns computed average value.
  66  */
  67 static uint8_t batadv_ring_buffer_avg(const uint8_t lq_recv[])
  68 {
  69         const uint8_t *ptr;
  70         uint16_t count = 0, i = 0, sum = 0;
  71
  72         ptr = lq_recv;
  73
  74         while (i < BATADV_TQ_GLOBAL_WINDOW_SIZE) {
  75                 if (*ptr != 0) {
  76                         count++;
  77                         sum += *ptr;
  78                 }
  79
  80                 i++;
  81                 ptr++;
  82         }
  83
  84         if (count == 0)
  85                 return 0;
  86
  87         return (uint8_t)(sum / count);
  88 }
  89
  90 /**
  91  * batadv_iv_ogm_orig_get - retrieve or create (if does not exist) an originator
  92  * @bat_priv: the bat priv with all the soft interface information
  93  * @addr: mac address of the originator
  94  *
  95  * Returns the originator object corresponding to the passed mac address or NULL
  96  * on failure.
  97  * If the object does not exists it is created an initialised.
  98  */
  99 static struct batadv_orig_node *
 100 batadv_iv_ogm_orig_get(struct batadv_priv *bat_priv, const uint8_t *addr)
 101 {
 102         struct batadv_orig_node *orig_node;
 103         int size, hash_added;
 104
 105         orig_node = batadv_orig_hash_find(bat_priv, addr);
 106         if (orig_node)
 107                 return orig_node;
 108
 109         orig_node = batadv_orig_node_new(bat_priv, addr);
 110         if (!orig_node)
 111                 return NULL;
 112
 113         spin_lock_init(&orig_node->bat_iv.ogm_cnt_lock);
 114
 115         size = bat_priv->num_ifaces * sizeof(unsigned long) * BATADV_NUM_WORDS;
 116         orig_node->bat_iv.bcast_own = kzalloc(size, GFP_ATOMIC);
 117         if (!orig_node->bat_iv.bcast_own)
 118                 goto free_orig_node;
 119
 120         size = bat_priv->num_ifaces * sizeof(uint8_t);
 121         orig_node->bat_iv.bcast_own_sum = kzalloc(size, GFP_ATOMIC);
 122         if (!orig_node->bat_iv.bcast_own_sum)
 123                 goto free_bcast_own;
 124
 125         hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig,
 126                                      batadv_choose_orig, orig_node,
 127                                      &orig_node->hash_entry);
 128         if (hash_added != 0)
 129                 goto free_bcast_own;
 130
 131         return orig_node;
 132
 133 free_bcast_own:
 134         kfree(orig_node->bat_iv.bcast_own);
 135 free_orig_node:
 136         batadv_orig_node_free_ref(orig_node);
 137
 138         return NULL;
 139 }
 140
 141 static struct batadv_neigh_node *
 142 batadv_iv_ogm_neigh_new(struct batadv_hard_iface *hard_iface,
 143                         const uint8_t *neigh_addr,
 144                         struct batadv_orig_node *orig_node,
 145                         struct batadv_orig_node *orig_neigh)
 146 {
 147         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 148         struct batadv_neigh_node *neigh_node;
 149
 150         neigh_node = batadv_neigh_node_new(hard_iface, neigh_addr, orig_node);
 151         if (!neigh_node)
 152                 goto out;
 153
 154         spin_lock_init(&neigh_node->bat_iv.lq_update_lock);
 155
 156         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 157                    "Creating new neighbor %pM for orig_node %pM on interface %s\n",
 158                    neigh_addr, orig_node->orig, hard_iface->net_dev->name);
 159
 160         spin_lock_bh(&orig_node->neigh_list_lock);
 161         hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list);
 162         spin_unlock_bh(&orig_node->neigh_list_lock);
 163
 164 out:
 165         return neigh_node;
 166 }
 167
 168 static int batadv_iv_ogm_iface_enable(struct batadv_hard_iface *hard_iface)
 169 {
 170         struct batadv_ogm_packet *batadv_ogm_packet;
 171         unsigned char *ogm_buff;
 172         uint32_t random_seqno;
 173         int res = -ENOMEM;
 174
 175         /* randomize initial seqno to avoid collision */
 176         get_random_bytes(&random_seqno, sizeof(random_seqno));
 177         atomic_set(&hard_iface->bat_iv.ogm_seqno, random_seqno);
 178
 179         hard_iface->bat_iv.ogm_buff_len = BATADV_OGM_HLEN;
 180         ogm_buff = kmalloc(hard_iface->bat_iv.ogm_buff_len, GFP_ATOMIC);
 181         if (!ogm_buff)
 182                 goto out;
 183
 184         hard_iface->bat_iv.ogm_buff = ogm_buff;
 185
 186         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 187         batadv_ogm_packet->header.packet_type = BATADV_IV_OGM;
 188         batadv_ogm_packet->header.version = BATADV_COMPAT_VERSION;
 189         batadv_ogm_packet->header.ttl = 2;
 190         batadv_ogm_packet->flags = BATADV_NO_FLAGS;
 191         batadv_ogm_packet->reserved = 0;
 192         batadv_ogm_packet->tq = BATADV_TQ_MAX_VALUE;
 193
 194         res = 0;
 195
 196 out:
 197         return res;
 198 }
 199
 200 static void batadv_iv_ogm_iface_disable(struct batadv_hard_iface *hard_iface)
 201 {
 202         kfree(hard_iface->bat_iv.ogm_buff);
 203         hard_iface->bat_iv.ogm_buff = NULL;
 204 }
 205
 206 static void batadv_iv_ogm_iface_update_mac(struct batadv_hard_iface *hard_iface)
 207 {
 208         struct batadv_ogm_packet *batadv_ogm_packet;
 209         unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
 210
 211         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 212         memcpy(batadv_ogm_packet->orig,
 213                hard_iface->net_dev->dev_addr, ETH_ALEN);
 214         memcpy(batadv_ogm_packet->prev_sender,
 215                hard_iface->net_dev->dev_addr, ETH_ALEN);
 216 }
 217
 218 static void
 219 batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface)
 220 {
 221         struct batadv_ogm_packet *batadv_ogm_packet;
 222         unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
 223
 224         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 225         batadv_ogm_packet->flags = BATADV_PRIMARIES_FIRST_HOP;
 226         batadv_ogm_packet->header.ttl = BATADV_TTL;
 227 }
 228
 229 /* when do we schedule our own ogm to be sent */
 230 static unsigned long
 231 batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
 232 {
 233         unsigned int msecs;
 234
 235         msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
 236         msecs += prandom_u32() % (2 * BATADV_JITTER);
 237
 238         return jiffies + msecs_to_jiffies(msecs);
 239 }
 240
 241 /* when do we schedule a ogm packet to be sent */
 242 static unsigned long batadv_iv_ogm_fwd_send_time(void)
 243 {
 244         return jiffies + msecs_to_jiffies(prandom_u32() % (BATADV_JITTER / 2));
 245 }
 246
 247 /* apply hop penalty for a normal link */
 248 static uint8_t batadv_hop_penalty(uint8_t tq,
 249                                   const struct batadv_priv *bat_priv)
 250 {
 251         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
 252         int new_tq;
 253
 254         new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty);
 255         new_tq /= BATADV_TQ_MAX_VALUE;
 256
 257         return new_tq;
 258 }
 259
 260 /* is there another aggregated packet here? */
 261 static int batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
 262                                      __be16 tvlv_len)
 263 {
 264         int next_buff_pos = 0;
 265
 266         next_buff_pos += buff_pos + BATADV_OGM_HLEN;
 267         next_buff_pos += ntohs(tvlv_len);
 268
 269         return (next_buff_pos <= packet_len) &&
 270                (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
 271 }
 272
 273 /* send a batman ogm to a given interface */
 274 static void batadv_iv_ogm_send_to_if(struct batadv_forw_packet *forw_packet,
 275                                      struct batadv_hard_iface *hard_iface)
 276 {
 277         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 278         char *fwd_str;
 279         uint8_t packet_num;
 280         int16_t buff_pos;
 281         struct batadv_ogm_packet *batadv_ogm_packet;
 282         struct sk_buff *skb;
 283         uint8_t *packet_pos;
 284
 285         if (hard_iface->if_status != BATADV_IF_ACTIVE)
 286                 return;
 287
 288         packet_num = 0;
 289         buff_pos = 0;
 290         packet_pos = forw_packet->skb->data;
 291         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 292
 293         /* adjust all flags and log packets */
 294         while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
 295                                          batadv_ogm_packet->tvlv_len)) {
 296                 /* we might have aggregated direct link packets with an
 297                  * ordinary base packet
 298                  */
 299                 if (forw_packet->direct_link_flags & BIT(packet_num) &&
 300                     forw_packet->if_incoming == hard_iface)
 301                         batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 302                 else
 303                         batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 304
 305                 if (packet_num > 0 || !forw_packet->own)
 306                         fwd_str = "Forwarding";
 307                 else
 308                         fwd_str = "Sending own";
 309
 310                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 311                            "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s) on interface %s [%pM]\n",
 312                            fwd_str, (packet_num > 0 ? "aggregated " : ""),
 313                            batadv_ogm_packet->orig,
 314                            ntohl(batadv_ogm_packet->seqno),
 315                            batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl,
 316                            (batadv_ogm_packet->flags & BATADV_DIRECTLINK ?
 317                             "on" : "off"),
 318                            hard_iface->net_dev->name,
 319                            hard_iface->net_dev->dev_addr);
 320
 321                 buff_pos += BATADV_OGM_HLEN;
 322                 buff_pos += ntohs(batadv_ogm_packet->tvlv_len);
 323                 packet_num++;
 324                 packet_pos = forw_packet->skb->data + buff_pos;
 325                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 326         }
 327
 328         /* create clone because function is called more than once */
 329         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
 330         if (skb) {
 331                 batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
 332                 batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
 333                                    skb->len + ETH_HLEN);
 334                 batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
 335         }
 336 }
 337
 338 /* send a batman ogm packet */
 339 static void batadv_iv_ogm_emit(struct batadv_forw_packet *forw_packet)
 340 {
 341         struct batadv_hard_iface *hard_iface;
 342         struct net_device *soft_iface;
 343         struct batadv_priv *bat_priv;
 344         struct batadv_hard_iface *primary_if = NULL;
 345         struct batadv_ogm_packet *batadv_ogm_packet;
 346         unsigned char directlink;
 347         uint8_t *packet_pos;
 348
 349         packet_pos = forw_packet->skb->data;
 350         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 351         directlink = (batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0);
 352
 353         if (!forw_packet->if_incoming) {
 354                 pr_err("Error - can't forward packet: incoming iface not specified\n");
 355                 goto out;
 356         }
 357
 358         soft_iface = forw_packet->if_incoming->soft_iface;
 359         bat_priv = netdev_priv(soft_iface);
 360
 361         if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE)
 362                 goto out;
 363
 364         primary_if = batadv_primary_if_get_selected(bat_priv);
 365         if (!primary_if)
 366                 goto out;
 367
 368         /* multihomed peer assumed
 369          * non-primary OGMs are only broadcasted on their interface
 370          */
 371         if ((directlink && (batadv_ogm_packet->header.ttl == 1)) ||
 372             (forw_packet->own && (forw_packet->if_incoming != primary_if))) {
 373                 /* FIXME: what about aggregated packets ? */
 374                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 375                            "%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n",
 376                            (forw_packet->own ? "Sending own" : "Forwarding"),
 377                            batadv_ogm_packet->orig,
 378                            ntohl(batadv_ogm_packet->seqno),
 379                            batadv_ogm_packet->header.ttl,
 380                            forw_packet->if_incoming->net_dev->name,
 381                            forw_packet->if_incoming->net_dev->dev_addr);
 382
 383                 /* skb is only used once and than forw_packet is free'd */
 384                 batadv_send_skb_packet(forw_packet->skb,
 385                                        forw_packet->if_incoming,
 386                                        batadv_broadcast_addr);
 387                 forw_packet->skb = NULL;
 388
 389                 goto out;
 390         }
 391
 392         /* broadcast on every interface */
 393         rcu_read_lock();
 394         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 395                 if (hard_iface->soft_iface != soft_iface)
 396                         continue;
 397
 398                 batadv_iv_ogm_send_to_if(forw_packet, hard_iface);
 399         }
 400         rcu_read_unlock();
 401
 402 out:
 403         if (primary_if)
 404                 batadv_hardif_free_ref(primary_if);
 405 }
 406
 407 /* return true if new_packet can be aggregated with forw_packet */
 408 static bool
 409 batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet,
 410                             struct batadv_priv *bat_priv,
 411                             int packet_len, unsigned long send_time,
 412                             bool directlink,
 413                             const struct batadv_hard_iface *if_incoming,
 414                             const struct batadv_forw_packet *forw_packet)
 415 {
 416         struct batadv_ogm_packet *batadv_ogm_packet;
 417         int aggregated_bytes = forw_packet->packet_len + packet_len;
 418         struct batadv_hard_iface *primary_if = NULL;
 419         bool res = false;
 420         unsigned long aggregation_end_time;
 421
 422         batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
 423         aggregation_end_time = send_time;
 424         aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 425
 426         /* we can aggregate the current packet to this aggregated packet
 427          * if:
 428          *
 429          * - the send time is within our MAX_AGGREGATION_MS time
 430          * - the resulting packet wont be bigger than
 431          *   MAX_AGGREGATION_BYTES
 432          */
 433         if (time_before(send_time, forw_packet->send_time) &&
 434             time_after_eq(aggregation_end_time, forw_packet->send_time) &&
 435             (aggregated_bytes <= BATADV_MAX_AGGREGATION_BYTES)) {
 436                 /* check aggregation compatibility
 437                  * -> direct link packets are broadcasted on
 438                  *    their interface only
 439                  * -> aggregate packet if the current packet is
 440                  *    a "global" packet as well as the base
 441                  *    packet
 442                  */
 443                 primary_if = batadv_primary_if_get_selected(bat_priv);
 444                 if (!primary_if)
 445                         goto out;
 446
 447                 /* packets without direct link flag and high TTL
 448                  * are flooded through the net
 449                  */
 450                 if ((!directlink) &&
 451                     (!(batadv_ogm_packet->flags & BATADV_DIRECTLINK)) &&
 452                     (batadv_ogm_packet->header.ttl != 1) &&
 453
 454                     /* own packets originating non-primary
 455                      * interfaces leave only that interface
 456                      */
 457                     ((!forw_packet->own) ||
 458                      (forw_packet->if_incoming == primary_if))) {
 459                         res = true;
 460                         goto out;
 461                 }
 462
 463                 /* if the incoming packet is sent via this one
 464                  * interface only - we still can aggregate
 465                  */
 466                 if ((directlink) &&
 467                     (new_bat_ogm_packet->header.ttl == 1) &&
 468                     (forw_packet->if_incoming == if_incoming) &&
 469
 470                     /* packets from direct neighbors or
 471                      * own secondary interface packets
 472                      * (= secondary interface packets in general)
 473                      */
 474                     (batadv_ogm_packet->flags & BATADV_DIRECTLINK ||
 475                      (forw_packet->own &&
 476                       forw_packet->if_incoming != primary_if))) {
 477                         res = true;
 478                         goto out;
 479                 }
 480         }
 481
 482 out:
 483         if (primary_if)
 484                 batadv_hardif_free_ref(primary_if);
 485         return res;
 486 }
 487
 488 /* create a new aggregated packet and add this packet to it */
 489 static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 490                                         int packet_len, unsigned long send_time,
 491                                         bool direct_link,
 492                                         struct batadv_hard_iface *if_incoming,
 493                                         int own_packet)
 494 {
 495         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 496         struct batadv_forw_packet *forw_packet_aggr;
 497         unsigned char *skb_buff;
 498         unsigned int skb_size;
 499
 500         if (!atomic_inc_not_zero(&if_incoming->refcount))
 501                 return;
 502
 503         /* own packet should always be scheduled */
 504         if (!own_packet) {
 505                 if (!batadv_atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
 506                         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 507                                    "batman packet queue full\n");
 508                         goto out;
 509                 }
 510         }
 511
 512         forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
 513         if (!forw_packet_aggr) {
 514                 if (!own_packet)
 515                         atomic_inc(&bat_priv->batman_queue_left);
 516                 goto out;
 517         }
 518
 519         if ((atomic_read(&bat_priv->aggregated_ogms)) &&
 520             (packet_len < BATADV_MAX_AGGREGATION_BYTES))
 521                 skb_size = BATADV_MAX_AGGREGATION_BYTES;
 522         else
 523                 skb_size = packet_len;
 524
 525         skb_size += ETH_HLEN;
 526
 527         forw_packet_aggr->skb = netdev_alloc_skb_ip_align(NULL, skb_size);
 528         if (!forw_packet_aggr->skb) {
 529                 if (!own_packet)
 530                         atomic_inc(&bat_priv->batman_queue_left);
 531                 kfree(forw_packet_aggr);
 532                 goto out;
 533         }
 534         forw_packet_aggr->skb->priority = TC_PRIO_CONTROL;
 535         skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
 536
 537         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 538         forw_packet_aggr->packet_len = packet_len;
 539         memcpy(skb_buff, packet_buff, packet_len);
 540
 541         forw_packet_aggr->own = own_packet;
 542         forw_packet_aggr->if_incoming = if_incoming;
 543         forw_packet_aggr->num_packets = 0;
 544         forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
 545         forw_packet_aggr->send_time = send_time;
 546
 547         /* save packet direct link flag status */
 548         if (direct_link)
 549                 forw_packet_aggr->direct_link_flags |= 1;
 550
 551         /* add new packet to packet list */
 552         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 553         hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
 554         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 555
 556         /* start timer for this packet */
 557         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 558                           batadv_send_outstanding_bat_ogm_packet);
 559         queue_delayed_work(batadv_event_workqueue,
 560                            &forw_packet_aggr->delayed_work,
 561                            send_time - jiffies);
 562
 563         return;
 564 out:
 565         batadv_hardif_free_ref(if_incoming);
 566 }
 567
 568 /* aggregate a new packet into the existing ogm packet */
 569 static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr,
 570                                     const unsigned char *packet_buff,
 571                                     int packet_len, bool direct_link)
 572 {
 573         unsigned char *skb_buff;
 574         unsigned long new_direct_link_flag;
 575
 576         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 577         memcpy(skb_buff, packet_buff, packet_len);
 578         forw_packet_aggr->packet_len += packet_len;
 579         forw_packet_aggr->num_packets++;
 580
 581         /* save packet direct link flag status */
 582         if (direct_link) {
 583                 new_direct_link_flag = BIT(forw_packet_aggr->num_packets);
 584                 forw_packet_aggr->direct_link_flags |= new_direct_link_flag;
 585         }
 586 }
 587
 588 static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv,
 589                                     unsigned char *packet_buff,
 590                                     int packet_len,
 591                                     struct batadv_hard_iface *if_incoming,
 592                                     int own_packet, unsigned long send_time)
 593 {
 594         /* _aggr -> pointer to the packet we want to aggregate with
 595          * _pos -> pointer to the position in the queue
 596          */
 597         struct batadv_forw_packet *forw_packet_aggr = NULL;
 598         struct batadv_forw_packet *forw_packet_pos = NULL;
 599         struct batadv_ogm_packet *batadv_ogm_packet;
 600         bool direct_link;
 601         unsigned long max_aggregation_jiffies;
 602
 603         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
 604         direct_link = batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0;
 605         max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 606
 607         /* find position for the packet in the forward queue */
 608         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 609         /* own packets are not to be aggregated */
 610         if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
 611                 hlist_for_each_entry(forw_packet_pos,
 612                                      &bat_priv->forw_bat_list, list) {
 613                         if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet,
 614                                                         bat_priv, packet_len,
 615                                                         send_time, direct_link,
 616                                                         if_incoming,
 617                                                         forw_packet_pos)) {
 618                                 forw_packet_aggr = forw_packet_pos;
 619                                 break;
 620                         }
 621                 }
 622         }
 623
 624         /* nothing to aggregate with - either aggregation disabled or no
 625          * suitable aggregation packet found
 626          */
 627         if (!forw_packet_aggr) {
 628                 /* the following section can run without the lock */
 629                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 630
 631                 /* if we could not aggregate this packet with one of the others
 632                  * we hold it back for a while, so that it might be aggregated
 633                  * later on
 634                  */
 635                 if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
 636                         send_time += max_aggregation_jiffies;
 637
 638                 batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
 639                                             send_time, direct_link,
 640                                             if_incoming, own_packet);
 641         } else {
 642                 batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 643                                         packet_len, direct_link);
 644                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 645         }
 646 }
 647
 648 static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
 649                                   const struct ethhdr *ethhdr,
 650                                   struct batadv_ogm_packet *batadv_ogm_packet,
 651                                   bool is_single_hop_neigh,
 652                                   bool is_from_best_next_hop,
 653                                   struct batadv_hard_iface *if_incoming)
 654 {
 655         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 656         uint16_t tvlv_len;
 657
 658         if (batadv_ogm_packet->header.ttl <= 1) {
 659                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
 660                 return;
 661         }
 662
 663         if (!is_from_best_next_hop) {
 664                 /* Mark the forwarded packet when it is not coming from our
 665                  * best next hop. We still need to forward the packet for our
 666                  * neighbor link quality detection to work in case the packet
 667                  * originated from a single hop neighbor. Otherwise we can
 668                  * simply drop the ogm.
 669                  */
 670                 if (is_single_hop_neigh)
 671                         batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP;
 672                 else
 673                         return;
 674         }
 675
 676         tvlv_len = ntohs(batadv_ogm_packet->tvlv_len);
 677
 678         batadv_ogm_packet->header.ttl--;
 679         memcpy(batadv_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 680
 681         /* apply hop penalty */
 682         batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq,
 683                                                    bat_priv);
 684
 685         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 686                    "Forwarding packet: tq: %i, ttl: %i\n",
 687                    batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl);
 688
 689         /* switch of primaries first hop flag when forwarding */
 690         batadv_ogm_packet->flags &= ~BATADV_PRIMARIES_FIRST_HOP;
 691         if (is_single_hop_neigh)
 692                 batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 693         else
 694                 batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 695
 696         batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
 697                                 BATADV_OGM_HLEN + tvlv_len,
 698                                 if_incoming, 0, batadv_iv_ogm_fwd_send_time());
 699 }
 700
 701 /**
 702  * batadv_iv_ogm_slide_own_bcast_window - bitshift own OGM broadcast windows for
 703  * the given interface
 704  * @hard_iface: the interface for which the windows have to be shifted
 705  */
 706 static void
 707 batadv_iv_ogm_slide_own_bcast_window(struct batadv_hard_iface *hard_iface)
 708 {
 709         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 710         struct batadv_hashtable *hash = bat_priv->orig_hash;
 711         struct hlist_head *head;
 712         struct batadv_orig_node *orig_node;
 713         unsigned long *word;
 714         uint32_t i;
 715         size_t word_index;
 716         uint8_t *w;
 717         int if_num;
 718
 719         for (i = 0; i < hash->size; i++) {
 720                 head = &hash->table[i];
 721
 722                 rcu_read_lock();
 723                 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
 724                         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 725                         word_index = hard_iface->if_num * BATADV_NUM_WORDS;
 726                         word = &(orig_node->bat_iv.bcast_own[word_index]);
 727
 728                         batadv_bit_get_packet(bat_priv, word, 1, 0);
 729                         if_num = hard_iface->if_num;
 730                         w = &orig_node->bat_iv.bcast_own_sum[if_num];
 731                         *w = bitmap_weight(word, BATADV_TQ_LOCAL_WINDOW_SIZE);
 732                         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 733                 }
 734                 rcu_read_unlock();
 735         }
 736 }
 737
 738 static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
 739 {
 740         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 741         unsigned char **ogm_buff = &hard_iface->bat_iv.ogm_buff;
 742         struct batadv_ogm_packet *batadv_ogm_packet;
 743         struct batadv_hard_iface *primary_if;
 744         int *ogm_buff_len = &hard_iface->bat_iv.ogm_buff_len;
 745         uint32_t seqno;
 746         uint16_t tvlv_len = 0;
 747
 748         primary_if = batadv_primary_if_get_selected(bat_priv);
 749
 750         if (hard_iface == primary_if) {
 751                 /* tt changes have to be committed before the tvlv data is
 752                  * appended as it may alter the tt tvlv container
 753                  */
 754                 batadv_tt_local_commit_changes(bat_priv);
 755                 tvlv_len = batadv_tvlv_container_ogm_append(bat_priv, ogm_buff,
 756                                                             ogm_buff_len,
 757                                                             BATADV_OGM_HLEN);
 758         }
 759
 760         batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff);
 761         batadv_ogm_packet->tvlv_len = htons(tvlv_len);
 762
 763         /* change sequence number to network order */
 764         seqno = (uint32_t)atomic_read(&hard_iface->bat_iv.ogm_seqno);
 765         batadv_ogm_packet->seqno = htonl(seqno);
 766         atomic_inc(&hard_iface->bat_iv.ogm_seqno);
 767
 768         batadv_iv_ogm_slide_own_bcast_window(hard_iface);
 769         batadv_iv_ogm_queue_add(bat_priv, hard_iface->bat_iv.ogm_buff,
 770                                 hard_iface->bat_iv.ogm_buff_len, hard_iface, 1,
 771                                 batadv_iv_ogm_emit_send_time(bat_priv));
 772
 773         if (primary_if)
 774                 batadv_hardif_free_ref(primary_if);
 775 }
 776
 777 static void
 778 batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv,
 779                           struct batadv_orig_node *orig_node,
 780                           const struct ethhdr *ethhdr,
 781                           const struct batadv_ogm_packet *batadv_ogm_packet,
 782                           struct batadv_hard_iface *if_incoming,
 783                           const unsigned char *tt_buff,
 784                           enum batadv_dup_status dup_status)
 785 {
 786         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 787         struct batadv_neigh_node *router = NULL;
 788         struct batadv_orig_node *orig_node_tmp;
 789         int if_num;
 790         uint8_t sum_orig, sum_neigh;
 791         uint8_t *neigh_addr;
 792         uint8_t tq_avg;
 793
 794         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 795                    "update_originator(): Searching and updating originator entry of received packet\n");
 796
 797         rcu_read_lock();
 798         hlist_for_each_entry_rcu(tmp_neigh_node,
 799                                  &orig_node->neigh_list, list) {
 800                 neigh_addr = tmp_neigh_node->addr;
 801                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 802                     tmp_neigh_node->if_incoming == if_incoming &&
 803                     atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
 804                         if (WARN(neigh_node, "too many matching neigh_nodes"))
 805                                 batadv_neigh_node_free_ref(neigh_node);
 806                         neigh_node = tmp_neigh_node;
 807                         continue;
 808                 }
 809
 810                 if (dup_status != BATADV_NO_DUP)
 811                         continue;
 812
 813                 spin_lock_bh(&tmp_neigh_node->bat_iv.lq_update_lock);
 814                 batadv_ring_buffer_set(tmp_neigh_node->bat_iv.tq_recv,
 815                                        &tmp_neigh_node->bat_iv.tq_index, 0);
 816                 tq_avg = batadv_ring_buffer_avg(tmp_neigh_node->bat_iv.tq_recv);
 817                 tmp_neigh_node->bat_iv.tq_avg = tq_avg;
 818                 spin_unlock_bh(&tmp_neigh_node->bat_iv.lq_update_lock);
 819         }
 820
 821         if (!neigh_node) {
 822                 struct batadv_orig_node *orig_tmp;
 823
 824                 orig_tmp = batadv_iv_ogm_orig_get(bat_priv, ethhdr->h_source);
 825                 if (!orig_tmp)
 826                         goto unlock;
 827
 828                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 829                                                      ethhdr->h_source,
 830                                                      orig_node, orig_tmp);
 831
 832                 batadv_orig_node_free_ref(orig_tmp);
 833                 if (!neigh_node)
 834                         goto unlock;
 835         } else
 836                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 837                            "Updating existing last-hop neighbor of originator\n");
 838
 839         rcu_read_unlock();
 840
 841         neigh_node->last_seen = jiffies;
 842
 843         spin_lock_bh(&neigh_node->bat_iv.lq_update_lock);
 844         batadv_ring_buffer_set(neigh_node->bat_iv.tq_recv,
 845                                &neigh_node->bat_iv.tq_index,
 846                                batadv_ogm_packet->tq);
 847         tq_avg = batadv_ring_buffer_avg(neigh_node->bat_iv.tq_recv);
 848         neigh_node->bat_iv.tq_avg = tq_avg;
 849         spin_unlock_bh(&neigh_node->bat_iv.lq_update_lock);
 850
 851         if (dup_status == BATADV_NO_DUP) {
 852                 orig_node->last_ttl = batadv_ogm_packet->header.ttl;
 853                 neigh_node->last_ttl = batadv_ogm_packet->header.ttl;
 854         }
 855
 856         batadv_bonding_candidate_add(orig_node, neigh_node);
 857
 858         /* if this neighbor already is our next hop there is nothing
 859          * to change
 860          */
 861         router = batadv_orig_node_get_router(orig_node);
 862         if (router == neigh_node)
 863                 goto out;
 864
 865         /* if this neighbor does not offer a better TQ we won't consider it */
 866         if (router && (router->bat_iv.tq_avg > neigh_node->bat_iv.tq_avg))
 867                 goto out;
 868
 869         /* if the TQ is the same and the link not more symmetric we
 870          * won't consider it either
 871          */
 872         if (router && (neigh_node->bat_iv.tq_avg == router->bat_iv.tq_avg)) {
 873                 orig_node_tmp = router->orig_node;
 874                 spin_lock_bh(&orig_node_tmp->bat_iv.ogm_cnt_lock);
 875                 if_num = router->if_incoming->if_num;
 876                 sum_orig = orig_node_tmp->bat_iv.bcast_own_sum[if_num];
 877                 spin_unlock_bh(&orig_node_tmp->bat_iv.ogm_cnt_lock);
 878
 879                 orig_node_tmp = neigh_node->orig_node;
 880                 spin_lock_bh(&orig_node_tmp->bat_iv.ogm_cnt_lock);
 881                 if_num = neigh_node->if_incoming->if_num;
 882                 sum_neigh = orig_node_tmp->bat_iv.bcast_own_sum[if_num];
 883                 spin_unlock_bh(&orig_node_tmp->bat_iv.ogm_cnt_lock);
 884
 885                 if (sum_orig >= sum_neigh)
 886                         goto out;
 887         }
 888
 889         batadv_update_route(bat_priv, orig_node, neigh_node);
 890         goto out;
 891
 892 unlock:
 893         rcu_read_unlock();
 894 out:
 895         if (neigh_node)
 896                 batadv_neigh_node_free_ref(neigh_node);
 897         if (router)
 898                 batadv_neigh_node_free_ref(router);
 899 }
 900
 901 static int batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
 902                                  struct batadv_orig_node *orig_neigh_node,
 903                                  struct batadv_ogm_packet *batadv_ogm_packet,
 904                                  struct batadv_hard_iface *if_incoming)
 905 {
 906         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 907         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node;
 908         uint8_t total_count;
 909         uint8_t orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
 910         unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
 911         int tq_asym_penalty, inv_asym_penalty, if_num, ret = 0;
 912         unsigned int combined_tq;
 913
 914         /* find corresponding one hop neighbor */
 915         rcu_read_lock();
 916         hlist_for_each_entry_rcu(tmp_neigh_node,
 917                                  &orig_neigh_node->neigh_list, list) {
 918                 if (!batadv_compare_eth(tmp_neigh_node->addr,
 919                                         orig_neigh_node->orig))
 920                         continue;
 921
 922                 if (tmp_neigh_node->if_incoming != if_incoming)
 923                         continue;
 924
 925                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 926                         continue;
 927
 928                 neigh_node = tmp_neigh_node;
 929                 break;
 930         }
 931         rcu_read_unlock();
 932
 933         if (!neigh_node)
 934                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 935                                                      orig_neigh_node->orig,
 936                                                      orig_neigh_node,
 937                                                      orig_neigh_node);
 938
 939         if (!neigh_node)
 940                 goto out;
 941
 942         /* if orig_node is direct neighbor update neigh_node last_seen */
 943         if (orig_node == orig_neigh_node)
 944                 neigh_node->last_seen = jiffies;
 945
 946         orig_node->last_seen = jiffies;
 947
 948         /* find packet count of corresponding one hop neighbor */
 949         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 950         if_num = if_incoming->if_num;
 951         orig_eq_count = orig_neigh_node->bat_iv.bcast_own_sum[if_num];
 952         neigh_rq_count = neigh_node->bat_iv.real_packet_count;
 953         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 954
 955         /* pay attention to not get a value bigger than 100 % */
 956         if (orig_eq_count > neigh_rq_count)
 957                 total_count = neigh_rq_count;
 958         else
 959                 total_count = orig_eq_count;
 960
 961         /* if we have too few packets (too less data) we set tq_own to zero
 962          * if we receive too few packets it is not considered bidirectional
 963          */
 964         if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
 965             neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
 966                 tq_own = 0;
 967         else
 968                 /* neigh_node->real_packet_count is never zero as we
 969                  * only purge old information when getting new
 970                  * information
 971                  */
 972                 tq_own = (BATADV_TQ_MAX_VALUE * total_count) /  neigh_rq_count;
 973
 974         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 975          * affect the nearly-symmetric links only a little, but
 976          * punishes asymmetric links more.  This will give a value
 977          * between 0 and TQ_MAX_VALUE
 978          */
 979         neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
 980         neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
 981         neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
 982                             BATADV_TQ_LOCAL_WINDOW_SIZE *
 983                             BATADV_TQ_LOCAL_WINDOW_SIZE;
 984         inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
 985         inv_asym_penalty /= neigh_rq_max_cube;
 986         tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;
 987
 988         combined_tq = batadv_ogm_packet->tq * tq_own * tq_asym_penalty;
 989         combined_tq /= BATADV_TQ_MAX_VALUE * BATADV_TQ_MAX_VALUE;
 990         batadv_ogm_packet->tq = combined_tq;
 991
 992         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 993                    "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n",
 994                    orig_node->orig, orig_neigh_node->orig, total_count,
 995                    neigh_rq_count, tq_own,
 996                    tq_asym_penalty, batadv_ogm_packet->tq);
 997
 998         /* if link has the minimum required transmission quality
 999          * consider it bidirectional
1000          */
1001         if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
1002                 ret = 1;
1003
1004 out:
1005         if (neigh_node)
1006                 batadv_neigh_node_free_ref(neigh_node);
1007         return ret;
1008 }
1009
1010 /**
1011  * batadv_iv_ogm_update_seqnos -  process a batman packet for all interfaces,
1012  *  adjust the sequence number and find out whether it is a duplicate
1013  * @ethhdr: ethernet header of the packet
1014  * @batadv_ogm_packet: OGM packet to be considered
1015  * @if_incoming: interface on which the OGM packet was received
1016  *
1017  * Returns duplicate status as enum batadv_dup_status
1018  */
1019 static enum batadv_dup_status
1020 batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
1021                             const struct batadv_ogm_packet *batadv_ogm_packet,
1022                             const struct batadv_hard_iface *if_incoming)
1023 {
1024         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1025         struct batadv_orig_node *orig_node;
1026         struct batadv_neigh_node *tmp_neigh_node;
1027         int is_dup;
1028         int32_t seq_diff;
1029         int need_update = 0;
1030         int set_mark;
1031         enum batadv_dup_status ret = BATADV_NO_DUP;
1032         uint32_t seqno = ntohl(batadv_ogm_packet->seqno);
1033         uint8_t *neigh_addr;
1034         uint8_t packet_count;
1035         unsigned long *bitmap;
1036
1037         orig_node = batadv_iv_ogm_orig_get(bat_priv, batadv_ogm_packet->orig);
1038         if (!orig_node)
1039                 return BATADV_NO_DUP;
1040
1041         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1042         seq_diff = seqno - orig_node->last_real_seqno;
1043
1044         /* signalize caller that the packet is to be dropped. */
1045         if (!hlist_empty(&orig_node->neigh_list) &&
1046             batadv_window_protected(bat_priv, seq_diff,
1047                                     &orig_node->batman_seqno_reset)) {
1048                 ret = BATADV_PROTECTED;
1049                 goto out;
1050         }
1051
1052         rcu_read_lock();
1053         hlist_for_each_entry_rcu(tmp_neigh_node,
1054                                  &orig_node->neigh_list, list) {
1055                 neigh_addr = tmp_neigh_node->addr;
1056                 is_dup = batadv_test_bit(tmp_neigh_node->bat_iv.real_bits,
1057                                          orig_node->last_real_seqno,
1058                                          seqno);
1059
1060                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
1061                     tmp_neigh_node->if_incoming == if_incoming) {
1062                         set_mark = 1;
1063                         if (is_dup)
1064                                 ret = BATADV_NEIGH_DUP;
1065                 } else {
1066                         set_mark = 0;
1067                         if (is_dup && (ret != BATADV_NEIGH_DUP))
1068                                 ret = BATADV_ORIG_DUP;
1069                 }
1070
1071                 /* if the window moved, set the update flag. */
1072                 bitmap = tmp_neigh_node->bat_iv.real_bits;
1073                 need_update |= batadv_bit_get_packet(bat_priv, bitmap,
1074                                                      seq_diff, set_mark);
1075
1076                 packet_count = bitmap_weight(tmp_neigh_node->bat_iv.real_bits,
1077                                              BATADV_TQ_LOCAL_WINDOW_SIZE);
1078                 tmp_neigh_node->bat_iv.real_packet_count = packet_count;
1079         }
1080         rcu_read_unlock();
1081
1082         if (need_update) {
1083                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1084                            "updating last_seqno: old %u, new %u\n",
1085                            orig_node->last_real_seqno, seqno);
1086                 orig_node->last_real_seqno = seqno;
1087         }
1088
1089 out:
1090         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1091         batadv_orig_node_free_ref(orig_node);
1092         return ret;
1093 }
1094
1095 static void batadv_iv_ogm_process(const struct ethhdr *ethhdr,
1096                                   struct batadv_ogm_packet *batadv_ogm_packet,
1097                                   const unsigned char *tt_buff,
1098                                   struct batadv_hard_iface *if_incoming)
1099 {
1100         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1101         struct batadv_hard_iface *hard_iface;
1102         struct batadv_orig_node *orig_neigh_node, *orig_node, *orig_node_tmp;
1103         struct batadv_neigh_node *router = NULL, *router_router = NULL;
1104         struct batadv_neigh_node *orig_neigh_router = NULL;
1105         int has_directlink_flag;
1106         int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
1107         int is_bidirect;
1108         bool is_single_hop_neigh = false;
1109         bool is_from_best_next_hop = false;
1110         int sameseq, similar_ttl;
1111         enum batadv_dup_status dup_status;
1112         uint32_t if_incoming_seqno;
1113         uint8_t *prev_sender;
1114
1115         /* Silently drop when the batman packet is actually not a
1116          * correct packet.
1117          *
1118          * This might happen if a packet is padded (e.g. Ethernet has a
1119          * minimum frame length of 64 byte) and the aggregation interprets
1120          * it as an additional length.
1121          *
1122          * TODO: A more sane solution would be to have a bit in the
1123          * batadv_ogm_packet to detect whether the packet is the last
1124          * packet in an aggregation.  Here we expect that the padding
1125          * is always zero (or not 0x01)
1126          */
1127         if (batadv_ogm_packet->header.packet_type != BATADV_IV_OGM)
1128                 return;
1129
1130         /* could be changed by schedule_own_packet() */
1131         if_incoming_seqno = atomic_read(&if_incoming->bat_iv.ogm_seqno);
1132
1133         if (batadv_ogm_packet->flags & BATADV_DIRECTLINK)
1134                 has_directlink_flag = 1;
1135         else
1136                 has_directlink_flag = 0;
1137
1138         if (batadv_compare_eth(ethhdr->h_source, batadv_ogm_packet->orig))
1139                 is_single_hop_neigh = true;
1140
1141         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1142                    "Received BATMAN packet via NB: %pM, IF: %s [%pM] (from OG: %pM, via prev OG: %pM, seqno %u, tq %d, TTL %d, V %d, IDF %d)\n",
1143                    ethhdr->h_source, if_incoming->net_dev->name,
1144                    if_incoming->net_dev->dev_addr, batadv_ogm_packet->orig,
1145                    batadv_ogm_packet->prev_sender,
1146                    ntohl(batadv_ogm_packet->seqno), batadv_ogm_packet->tq,
1147                    batadv_ogm_packet->header.ttl,
1148                    batadv_ogm_packet->header.version, has_directlink_flag);
1149
1150         rcu_read_lock();
1151         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1152                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
1153                         continue;
1154
1155                 if (hard_iface->soft_iface != if_incoming->soft_iface)
1156                         continue;
1157
1158                 if (batadv_compare_eth(ethhdr->h_source,
1159                                        hard_iface->net_dev->dev_addr))
1160                         is_my_addr = 1;
1161
1162                 if (batadv_compare_eth(batadv_ogm_packet->orig,
1163                                        hard_iface->net_dev->dev_addr))
1164                         is_my_orig = 1;
1165
1166                 if (batadv_compare_eth(batadv_ogm_packet->prev_sender,
1167                                        hard_iface->net_dev->dev_addr))
1168                         is_my_oldorig = 1;
1169         }
1170         rcu_read_unlock();
1171
1172         if (is_my_addr) {
1173                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1174                            "Drop packet: received my own broadcast (sender: %pM)\n",
1175                            ethhdr->h_source);
1176                 return;
1177         }
1178
1179         if (is_my_orig) {
1180                 unsigned long *word;
1181                 int offset;
1182                 int32_t bit_pos;
1183                 int16_t if_num;
1184                 uint8_t *weight;
1185
1186                 orig_neigh_node = batadv_iv_ogm_orig_get(bat_priv,
1187                                                          ethhdr->h_source);
1188                 if (!orig_neigh_node)
1189                         return;
1190
1191                 /* neighbor has to indicate direct link and it has to
1192                  * come via the corresponding interface
1193                  * save packet seqno for bidirectional check
1194                  */
1195                 if (has_directlink_flag &&
1196                     batadv_compare_eth(if_incoming->net_dev->dev_addr,
1197                                        batadv_ogm_packet->orig)) {
1198                         if_num = if_incoming->if_num;
1199                         offset = if_num * BATADV_NUM_WORDS;
1200
1201                         spin_lock_bh(&orig_neigh_node->bat_iv.ogm_cnt_lock);
1202                         word = &(orig_neigh_node->bat_iv.bcast_own[offset]);
1203                         bit_pos = if_incoming_seqno - 2;
1204                         bit_pos -= ntohl(batadv_ogm_packet->seqno);
1205                         batadv_set_bit(word, bit_pos);
1206                         weight = &orig_neigh_node->bat_iv.bcast_own_sum[if_num];
1207                         *weight = bitmap_weight(word,
1208                                                 BATADV_TQ_LOCAL_WINDOW_SIZE);
1209                         spin_unlock_bh(&orig_neigh_node->bat_iv.ogm_cnt_lock);
1210                 }
1211
1212                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1213                            "Drop packet: originator packet from myself (via neighbor)\n");
1214                 batadv_orig_node_free_ref(orig_neigh_node);
1215                 return;
1216         }
1217
1218         if (is_my_oldorig) {
1219                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1220                            "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1221                            ethhdr->h_source);
1222                 return;
1223         }
1224
1225         if (batadv_ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) {
1226                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1227                            "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1228                            ethhdr->h_source);
1229                 return;
1230         }
1231
1232         orig_node = batadv_iv_ogm_orig_get(bat_priv, batadv_ogm_packet->orig);
1233         if (!orig_node)
1234                 return;
1235
1236         dup_status = batadv_iv_ogm_update_seqnos(ethhdr, batadv_ogm_packet,
1237                                                  if_incoming);
1238
1239         if (dup_status == BATADV_PROTECTED) {
1240                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1241                            "Drop packet: packet within seqno protection time (sender: %pM)\n",
1242                            ethhdr->h_source);
1243                 goto out;
1244         }
1245
1246         if (batadv_ogm_packet->tq == 0) {
1247                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1248                            "Drop packet: originator packet with tq equal 0\n");
1249                 goto out;
1250         }
1251
1252         router = batadv_orig_node_get_router(orig_node);
1253         if (router) {
1254                 orig_node_tmp = router->orig_node;
1255                 router_router = batadv_orig_node_get_router(orig_node_tmp);
1256         }
1257
1258         if ((router && router->bat_iv.tq_avg != 0) &&
1259             (batadv_compare_eth(router->addr, ethhdr->h_source)))
1260                 is_from_best_next_hop = true;
1261
1262         prev_sender = batadv_ogm_packet->prev_sender;
1263         /* avoid temporary routing loops */
1264         if (router && router_router &&
1265             (batadv_compare_eth(router->addr, prev_sender)) &&
1266             !(batadv_compare_eth(batadv_ogm_packet->orig, prev_sender)) &&
1267             (batadv_compare_eth(router->addr, router_router->addr))) {
1268                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1269                            "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1270                            ethhdr->h_source);
1271                 goto out;
1272         }
1273
1274         batadv_tvlv_ogm_receive(bat_priv, batadv_ogm_packet, orig_node);
1275
1276         /* if sender is a direct neighbor the sender mac equals
1277          * originator mac
1278          */
1279         if (is_single_hop_neigh)
1280                 orig_neigh_node = orig_node;
1281         else
1282                 orig_neigh_node = batadv_iv_ogm_orig_get(bat_priv,
1283                                                          ethhdr->h_source);
1284
1285         if (!orig_neigh_node)
1286                 goto out;
1287
1288         /* Update nc_nodes of the originator */
1289         batadv_nc_update_nc_node(bat_priv, orig_node, orig_neigh_node,
1290                                  batadv_ogm_packet, is_single_hop_neigh);
1291
1292         orig_neigh_router = batadv_orig_node_get_router(orig_neigh_node);
1293
1294         /* drop packet if sender is not a direct neighbor and if we
1295          * don't route towards it
1296          */
1297         if (!is_single_hop_neigh && (!orig_neigh_router)) {
1298                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1299                            "Drop packet: OGM via unknown neighbor!\n");
1300                 goto out_neigh;
1301         }
1302
1303         is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1304                                             batadv_ogm_packet, if_incoming);
1305
1306         batadv_bonding_save_primary(orig_node, orig_neigh_node,
1307                                     batadv_ogm_packet);
1308
1309         /* update ranking if it is not a duplicate or has the same
1310          * seqno and similar ttl as the non-duplicate
1311          */
1312         sameseq = orig_node->last_real_seqno == ntohl(batadv_ogm_packet->seqno);
1313         similar_ttl = orig_node->last_ttl - 3 <= batadv_ogm_packet->header.ttl;
1314         if (is_bidirect && ((dup_status == BATADV_NO_DUP) ||
1315                             (sameseq && similar_ttl)))
1316                 batadv_iv_ogm_orig_update(bat_priv, orig_node, ethhdr,
1317                                           batadv_ogm_packet, if_incoming,
1318                                           tt_buff, dup_status);
1319
1320         /* is single hop (direct) neighbor */
1321         if (is_single_hop_neigh) {
1322                 /* mark direct link on incoming interface */
1323                 batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1324                                       is_single_hop_neigh,
1325                                       is_from_best_next_hop, if_incoming);
1326
1327                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1328                            "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1329                 goto out_neigh;
1330         }
1331
1332         /* multihop originator */
1333         if (!is_bidirect) {
1334                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1335                            "Drop packet: not received via bidirectional link\n");
1336                 goto out_neigh;
1337         }
1338
1339         if (dup_status == BATADV_NEIGH_DUP) {
1340                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1341                            "Drop packet: duplicate packet received\n");
1342                 goto out_neigh;
1343         }
1344
1345         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1346                    "Forwarding packet: rebroadcast originator packet\n");
1347         batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1348                               is_single_hop_neigh, is_from_best_next_hop,
1349                               if_incoming);
1350
1351 out_neigh:
1352         if ((orig_neigh_node) && (!is_single_hop_neigh))
1353                 batadv_orig_node_free_ref(orig_neigh_node);
1354 out:
1355         if (router)
1356                 batadv_neigh_node_free_ref(router);
1357         if (router_router)
1358                 batadv_neigh_node_free_ref(router_router);
1359         if (orig_neigh_router)
1360                 batadv_neigh_node_free_ref(orig_neigh_router);
1361
1362         batadv_orig_node_free_ref(orig_node);
1363 }
1364
1365 static int batadv_iv_ogm_receive(struct sk_buff *skb,
1366                                  struct batadv_hard_iface *if_incoming)
1367 {
1368         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1369         struct batadv_ogm_packet *batadv_ogm_packet;
1370         struct ethhdr *ethhdr;
1371         int buff_pos = 0, packet_len;
1372         unsigned char *tvlv_buff, *packet_buff;
1373         uint8_t *packet_pos;
1374         bool ret;
1375
1376         ret = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
1377         if (!ret)
1378                 return NET_RX_DROP;
1379
1380         /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1381          * that does not have B.A.T.M.A.N. IV enabled ?
1382          */
1383         if (bat_priv->bat_algo_ops->bat_ogm_emit != batadv_iv_ogm_emit)
1384                 return NET_RX_DROP;
1385
1386         batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
1387         batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
1388                            skb->len + ETH_HLEN);
1389
1390         packet_len = skb_headlen(skb);
1391         ethhdr = eth_hdr(skb);
1392         packet_buff = skb->data;
1393         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
1394
1395         /* unpack the aggregated packets and process them one by one */
1396         while (batadv_iv_ogm_aggr_packet(buff_pos, packet_len,
1397                                          batadv_ogm_packet->tvlv_len)) {
1398                 tvlv_buff = packet_buff + buff_pos + BATADV_OGM_HLEN;
1399
1400                 batadv_iv_ogm_process(ethhdr, batadv_ogm_packet,
1401                                       tvlv_buff, if_incoming);
1402
1403                 buff_pos += BATADV_OGM_HLEN;
1404                 buff_pos += ntohs(batadv_ogm_packet->tvlv_len);
1405
1406                 packet_pos = packet_buff + buff_pos;
1407                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
1408         }
1409
1410         kfree_skb(skb);
1411         return NET_RX_SUCCESS;
1412 }
1413
1414 static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
1415         .name = "BATMAN_IV",
1416         .bat_iface_enable = batadv_iv_ogm_iface_enable,
1417         .bat_iface_disable = batadv_iv_ogm_iface_disable,
1418         .bat_iface_update_mac = batadv_iv_ogm_iface_update_mac,
1419         .bat_primary_iface_set = batadv_iv_ogm_primary_iface_set,
1420         .bat_ogm_schedule = batadv_iv_ogm_schedule,
1421         .bat_ogm_emit = batadv_iv_ogm_emit,
1422 };
1423
1424 int __init batadv_iv_init(void)
1425 {
1426         int ret;
1427
1428         /* batman originator packet */
1429         ret = batadv_recv_handler_register(BATADV_IV_OGM,
1430                                            batadv_iv_ogm_receive);
1431         if (ret < 0)
1432                 goto out;
1433
1434         ret = batadv_algo_register(&batadv_batman_iv);
1435         if (ret < 0)
1436                 goto handler_unregister;
1437
1438         goto out;
1439
1440 handler_unregister:
1441         batadv_recv_handler_unregister(BATADV_IV_OGM);
1442 out:
1443         return ret;
1444 }