linux/net/batman-adv/bat_iv_ogm.c
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   1/* Copyright (C) 2007-2012 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 "ring_buffer.h"
  23#include "originator.h"
  24#include "routing.h"
  25#include "gateway_common.h"
  26#include "gateway_client.h"
  27#include "hard-interface.h"
  28#include "send.h"
  29#include "bat_algo.h"
  30
  31static struct batadv_neigh_node *
  32batadv_iv_ogm_neigh_new(struct batadv_hard_iface *hard_iface,
  33                        const uint8_t *neigh_addr,
  34                        struct batadv_orig_node *orig_node,
  35                        struct batadv_orig_node *orig_neigh, __be32 seqno)
  36{
  37        struct batadv_neigh_node *neigh_node;
  38
  39        neigh_node = batadv_neigh_node_new(hard_iface, neigh_addr,
  40                                           ntohl(seqno));
  41        if (!neigh_node)
  42                goto out;
  43
  44        INIT_LIST_HEAD(&neigh_node->bonding_list);
  45
  46        neigh_node->orig_node = orig_neigh;
  47        neigh_node->if_incoming = hard_iface;
  48
  49        spin_lock_bh(&orig_node->neigh_list_lock);
  50        hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list);
  51        spin_unlock_bh(&orig_node->neigh_list_lock);
  52
  53out:
  54        return neigh_node;
  55}
  56
  57static int batadv_iv_ogm_iface_enable(struct batadv_hard_iface *hard_iface)
  58{
  59        struct batadv_ogm_packet *batadv_ogm_packet;
  60        uint32_t random_seqno;
  61        int res = -ENOMEM;
  62
  63        /* randomize initial seqno to avoid collision */
  64        get_random_bytes(&random_seqno, sizeof(random_seqno));
  65        atomic_set(&hard_iface->seqno, random_seqno);
  66
  67        hard_iface->packet_len = BATADV_OGM_HLEN;
  68        hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC);
  69
  70        if (!hard_iface->packet_buff)
  71                goto out;
  72
  73        batadv_ogm_packet = (struct batadv_ogm_packet *)hard_iface->packet_buff;
  74        batadv_ogm_packet->header.packet_type = BATADV_IV_OGM;
  75        batadv_ogm_packet->header.version = BATADV_COMPAT_VERSION;
  76        batadv_ogm_packet->header.ttl = 2;
  77        batadv_ogm_packet->flags = BATADV_NO_FLAGS;
  78        batadv_ogm_packet->tq = BATADV_TQ_MAX_VALUE;
  79        batadv_ogm_packet->tt_num_changes = 0;
  80        batadv_ogm_packet->ttvn = 0;
  81
  82        res = 0;
  83
  84out:
  85        return res;
  86}
  87
  88static void batadv_iv_ogm_iface_disable(struct batadv_hard_iface *hard_iface)
  89{
  90        kfree(hard_iface->packet_buff);
  91        hard_iface->packet_buff = NULL;
  92}
  93
  94static void batadv_iv_ogm_iface_update_mac(struct batadv_hard_iface *hard_iface)
  95{
  96        struct batadv_ogm_packet *batadv_ogm_packet;
  97
  98        batadv_ogm_packet = (struct batadv_ogm_packet *)hard_iface->packet_buff;
  99        memcpy(batadv_ogm_packet->orig,
 100               hard_iface->net_dev->dev_addr, ETH_ALEN);
 101        memcpy(batadv_ogm_packet->prev_sender,
 102               hard_iface->net_dev->dev_addr, ETH_ALEN);
 103}
 104
 105static void
 106batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface)
 107{
 108        struct batadv_ogm_packet *batadv_ogm_packet;
 109
 110        batadv_ogm_packet = (struct batadv_ogm_packet *)hard_iface->packet_buff;
 111        batadv_ogm_packet->flags = BATADV_PRIMARIES_FIRST_HOP;
 112        batadv_ogm_packet->header.ttl = BATADV_TTL;
 113}
 114
 115/* when do we schedule our own ogm to be sent */
 116static unsigned long
 117batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
 118{
 119        unsigned int msecs;
 120
 121        msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
 122        msecs += (random32() % 2 * BATADV_JITTER);
 123
 124        return jiffies + msecs_to_jiffies(msecs);
 125}
 126
 127/* when do we schedule a ogm packet to be sent */
 128static unsigned long batadv_iv_ogm_fwd_send_time(void)
 129{
 130        return jiffies + msecs_to_jiffies(random32() % (BATADV_JITTER / 2));
 131}
 132
 133/* apply hop penalty for a normal link */
 134static uint8_t batadv_hop_penalty(uint8_t tq,
 135                                  const struct batadv_priv *bat_priv)
 136{
 137        int hop_penalty = atomic_read(&bat_priv->hop_penalty);
 138        int new_tq;
 139
 140        new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty);
 141        new_tq /= BATADV_TQ_MAX_VALUE;
 142
 143        return new_tq;
 144}
 145
 146/* is there another aggregated packet here? */
 147static int batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
 148                                     int tt_num_changes)
 149{
 150        int next_buff_pos = 0;
 151
 152        next_buff_pos += buff_pos + BATADV_OGM_HLEN;
 153        next_buff_pos += batadv_tt_len(tt_num_changes);
 154
 155        return (next_buff_pos <= packet_len) &&
 156               (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
 157}
 158
 159/* send a batman ogm to a given interface */
 160static void batadv_iv_ogm_send_to_if(struct batadv_forw_packet *forw_packet,
 161                                     struct batadv_hard_iface *hard_iface)
 162{
 163        struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 164        char *fwd_str;
 165        uint8_t packet_num;
 166        int16_t buff_pos;
 167        struct batadv_ogm_packet *batadv_ogm_packet;
 168        struct sk_buff *skb;
 169
 170        if (hard_iface->if_status != BATADV_IF_ACTIVE)
 171                return;
 172
 173        packet_num = 0;
 174        buff_pos = 0;
 175        batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
 176
 177        /* adjust all flags and log packets */
 178        while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
 179                                         batadv_ogm_packet->tt_num_changes)) {
 180
 181                /* we might have aggregated direct link packets with an
 182                 * ordinary base packet
 183                 */
 184                if ((forw_packet->direct_link_flags & (1 << packet_num)) &&
 185                    (forw_packet->if_incoming == hard_iface))
 186                        batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 187                else
 188                        batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 189
 190                fwd_str = (packet_num > 0 ? "Forwarding" : (forw_packet->own ?
 191                                                            "Sending own" :
 192                                                            "Forwarding"));
 193                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 194                           "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s, ttvn %d) on interface %s [%pM]\n",
 195                           fwd_str, (packet_num > 0 ? "aggregated " : ""),
 196                           batadv_ogm_packet->orig,
 197                           ntohl(batadv_ogm_packet->seqno),
 198                           batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl,
 199                           (batadv_ogm_packet->flags & BATADV_DIRECTLINK ?
 200                            "on" : "off"),
 201                           batadv_ogm_packet->ttvn, hard_iface->net_dev->name,
 202                           hard_iface->net_dev->dev_addr);
 203
 204                buff_pos += BATADV_OGM_HLEN;
 205                buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
 206                packet_num++;
 207                batadv_ogm_packet = (struct batadv_ogm_packet *)
 208                                        (forw_packet->skb->data + buff_pos);
 209        }
 210
 211        /* create clone because function is called more than once */
 212        skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
 213        if (skb) {
 214                batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
 215                batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
 216                                   skb->len + ETH_HLEN);
 217                batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
 218        }
 219}
 220
 221/* send a batman ogm packet */
 222static void batadv_iv_ogm_emit(struct batadv_forw_packet *forw_packet)
 223{
 224        struct batadv_hard_iface *hard_iface;
 225        struct net_device *soft_iface;
 226        struct batadv_priv *bat_priv;
 227        struct batadv_hard_iface *primary_if = NULL;
 228        struct batadv_ogm_packet *batadv_ogm_packet;
 229        unsigned char directlink;
 230
 231        batadv_ogm_packet = (struct batadv_ogm_packet *)
 232                                                (forw_packet->skb->data);
 233        directlink = (batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0);
 234
 235        if (!forw_packet->if_incoming) {
 236                pr_err("Error - can't forward packet: incoming iface not specified\n");
 237                goto out;
 238        }
 239
 240        soft_iface = forw_packet->if_incoming->soft_iface;
 241        bat_priv = netdev_priv(soft_iface);
 242
 243        if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE)
 244                goto out;
 245
 246        primary_if = batadv_primary_if_get_selected(bat_priv);
 247        if (!primary_if)
 248                goto out;
 249
 250        /* multihomed peer assumed
 251         * non-primary OGMs are only broadcasted on their interface
 252         */
 253        if ((directlink && (batadv_ogm_packet->header.ttl == 1)) ||
 254            (forw_packet->own && (forw_packet->if_incoming != primary_if))) {
 255
 256                /* FIXME: what about aggregated packets ? */
 257                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 258                           "%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n",
 259                           (forw_packet->own ? "Sending own" : "Forwarding"),
 260                           batadv_ogm_packet->orig,
 261                           ntohl(batadv_ogm_packet->seqno),
 262                           batadv_ogm_packet->header.ttl,
 263                           forw_packet->if_incoming->net_dev->name,
 264                           forw_packet->if_incoming->net_dev->dev_addr);
 265
 266                /* skb is only used once and than forw_packet is free'd */
 267                batadv_send_skb_packet(forw_packet->skb,
 268                                       forw_packet->if_incoming,
 269                                       batadv_broadcast_addr);
 270                forw_packet->skb = NULL;
 271
 272                goto out;
 273        }
 274
 275        /* broadcast on every interface */
 276        rcu_read_lock();
 277        list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 278                if (hard_iface->soft_iface != soft_iface)
 279                        continue;
 280
 281                batadv_iv_ogm_send_to_if(forw_packet, hard_iface);
 282        }
 283        rcu_read_unlock();
 284
 285out:
 286        if (primary_if)
 287                batadv_hardif_free_ref(primary_if);
 288}
 289
 290/* return true if new_packet can be aggregated with forw_packet */
 291static bool
 292batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet,
 293                            struct batadv_priv *bat_priv,
 294                            int packet_len, unsigned long send_time,
 295                            bool directlink,
 296                            const struct batadv_hard_iface *if_incoming,
 297                            const struct batadv_forw_packet *forw_packet)
 298{
 299        struct batadv_ogm_packet *batadv_ogm_packet;
 300        int aggregated_bytes = forw_packet->packet_len + packet_len;
 301        struct batadv_hard_iface *primary_if = NULL;
 302        bool res = false;
 303        unsigned long aggregation_end_time;
 304
 305        batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
 306        aggregation_end_time = send_time;
 307        aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 308
 309        /* we can aggregate the current packet to this aggregated packet
 310         * if:
 311         *
 312         * - the send time is within our MAX_AGGREGATION_MS time
 313         * - the resulting packet wont be bigger than
 314         *   MAX_AGGREGATION_BYTES
 315         */
 316        if (time_before(send_time, forw_packet->send_time) &&
 317            time_after_eq(aggregation_end_time, forw_packet->send_time) &&
 318            (aggregated_bytes <= BATADV_MAX_AGGREGATION_BYTES)) {
 319
 320                /* check aggregation compatibility
 321                 * -> direct link packets are broadcasted on
 322                 *    their interface only
 323                 * -> aggregate packet if the current packet is
 324                 *    a "global" packet as well as the base
 325                 *    packet
 326                 */
 327                primary_if = batadv_primary_if_get_selected(bat_priv);
 328                if (!primary_if)
 329                        goto out;
 330
 331                /* packets without direct link flag and high TTL
 332                 * are flooded through the net
 333                 */
 334                if ((!directlink) &&
 335                    (!(batadv_ogm_packet->flags & BATADV_DIRECTLINK)) &&
 336                    (batadv_ogm_packet->header.ttl != 1) &&
 337
 338                    /* own packets originating non-primary
 339                     * interfaces leave only that interface
 340                     */
 341                    ((!forw_packet->own) ||
 342                     (forw_packet->if_incoming == primary_if))) {
 343                        res = true;
 344                        goto out;
 345                }
 346
 347                /* if the incoming packet is sent via this one
 348                 * interface only - we still can aggregate
 349                 */
 350                if ((directlink) &&
 351                    (new_bat_ogm_packet->header.ttl == 1) &&
 352                    (forw_packet->if_incoming == if_incoming) &&
 353
 354                    /* packets from direct neighbors or
 355                     * own secondary interface packets
 356                     * (= secondary interface packets in general)
 357                     */
 358                    (batadv_ogm_packet->flags & BATADV_DIRECTLINK ||
 359                     (forw_packet->own &&
 360                      forw_packet->if_incoming != primary_if))) {
 361                        res = true;
 362                        goto out;
 363                }
 364        }
 365
 366out:
 367        if (primary_if)
 368                batadv_hardif_free_ref(primary_if);
 369        return res;
 370}
 371
 372/* create a new aggregated packet and add this packet to it */
 373static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 374                                        int packet_len, unsigned long send_time,
 375                                        bool direct_link,
 376                                        struct batadv_hard_iface *if_incoming,
 377                                        int own_packet)
 378{
 379        struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 380        struct batadv_forw_packet *forw_packet_aggr;
 381        unsigned char *skb_buff;
 382        unsigned int skb_size;
 383
 384        if (!atomic_inc_not_zero(&if_incoming->refcount))
 385                return;
 386
 387        /* own packet should always be scheduled */
 388        if (!own_packet) {
 389                if (!batadv_atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
 390                        batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 391                                   "batman packet queue full\n");
 392                        goto out;
 393                }
 394        }
 395
 396        forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
 397        if (!forw_packet_aggr) {
 398                if (!own_packet)
 399                        atomic_inc(&bat_priv->batman_queue_left);
 400                goto out;
 401        }
 402
 403        if ((atomic_read(&bat_priv->aggregated_ogms)) &&
 404            (packet_len < BATADV_MAX_AGGREGATION_BYTES))
 405                skb_size = BATADV_MAX_AGGREGATION_BYTES + ETH_HLEN;
 406        else
 407                skb_size = packet_len + ETH_HLEN;
 408
 409        forw_packet_aggr->skb = dev_alloc_skb(skb_size);
 410        if (!forw_packet_aggr->skb) {
 411                if (!own_packet)
 412                        atomic_inc(&bat_priv->batman_queue_left);
 413                kfree(forw_packet_aggr);
 414                goto out;
 415        }
 416        skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
 417
 418        INIT_HLIST_NODE(&forw_packet_aggr->list);
 419
 420        skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 421        forw_packet_aggr->packet_len = packet_len;
 422        memcpy(skb_buff, packet_buff, packet_len);
 423
 424        forw_packet_aggr->own = own_packet;
 425        forw_packet_aggr->if_incoming = if_incoming;
 426        forw_packet_aggr->num_packets = 0;
 427        forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
 428        forw_packet_aggr->send_time = send_time;
 429
 430        /* save packet direct link flag status */
 431        if (direct_link)
 432                forw_packet_aggr->direct_link_flags |= 1;
 433
 434        /* add new packet to packet list */
 435        spin_lock_bh(&bat_priv->forw_bat_list_lock);
 436        hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
 437        spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 438
 439        /* start timer for this packet */
 440        INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 441                          batadv_send_outstanding_bat_ogm_packet);
 442        queue_delayed_work(batadv_event_workqueue,
 443                           &forw_packet_aggr->delayed_work,
 444                           send_time - jiffies);
 445
 446        return;
 447out:
 448        batadv_hardif_free_ref(if_incoming);
 449}
 450
 451/* aggregate a new packet into the existing ogm packet */
 452static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr,
 453                                    const unsigned char *packet_buff,
 454                                    int packet_len, bool direct_link)
 455{
 456        unsigned char *skb_buff;
 457
 458        skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 459        memcpy(skb_buff, packet_buff, packet_len);
 460        forw_packet_aggr->packet_len += packet_len;
 461        forw_packet_aggr->num_packets++;
 462
 463        /* save packet direct link flag status */
 464        if (direct_link)
 465                forw_packet_aggr->direct_link_flags |=
 466                        (1 << forw_packet_aggr->num_packets);
 467}
 468
 469static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv,
 470                                    unsigned char *packet_buff,
 471                                    int packet_len,
 472                                    struct batadv_hard_iface *if_incoming,
 473                                    int own_packet, unsigned long send_time)
 474{
 475        /* _aggr -> pointer to the packet we want to aggregate with
 476         * _pos -> pointer to the position in the queue
 477         */
 478        struct batadv_forw_packet *forw_packet_aggr = NULL;
 479        struct batadv_forw_packet *forw_packet_pos = NULL;
 480        struct hlist_node *tmp_node;
 481        struct batadv_ogm_packet *batadv_ogm_packet;
 482        bool direct_link;
 483        unsigned long max_aggregation_jiffies;
 484
 485        batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
 486        direct_link = batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0;
 487        max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 488
 489        /* find position for the packet in the forward queue */
 490        spin_lock_bh(&bat_priv->forw_bat_list_lock);
 491        /* own packets are not to be aggregated */
 492        if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
 493                hlist_for_each_entry(forw_packet_pos, tmp_node,
 494                                     &bat_priv->forw_bat_list, list) {
 495                        if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet,
 496                                                        bat_priv, packet_len,
 497                                                        send_time, direct_link,
 498                                                        if_incoming,
 499                                                        forw_packet_pos)) {
 500                                forw_packet_aggr = forw_packet_pos;
 501                                break;
 502                        }
 503                }
 504        }
 505
 506        /* nothing to aggregate with - either aggregation disabled or no
 507         * suitable aggregation packet found
 508         */
 509        if (!forw_packet_aggr) {
 510                /* the following section can run without the lock */
 511                spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 512
 513                /* if we could not aggregate this packet with one of the others
 514                 * we hold it back for a while, so that it might be aggregated
 515                 * later on
 516                 */
 517                if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
 518                        send_time += max_aggregation_jiffies;
 519
 520                batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
 521                                            send_time, direct_link,
 522                                            if_incoming, own_packet);
 523        } else {
 524                batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 525                                        packet_len, direct_link);
 526                spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 527        }
 528}
 529
 530static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
 531                                  const struct ethhdr *ethhdr,
 532                                  struct batadv_ogm_packet *batadv_ogm_packet,
 533                                  bool is_single_hop_neigh,
 534                                  bool is_from_best_next_hop,
 535                                  struct batadv_hard_iface *if_incoming)
 536{
 537        struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 538        uint8_t tt_num_changes;
 539
 540        if (batadv_ogm_packet->header.ttl <= 1) {
 541                batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
 542                return;
 543        }
 544
 545        if (!is_from_best_next_hop) {
 546                /* Mark the forwarded packet when it is not coming from our
 547                 * best next hop. We still need to forward the packet for our
 548                 * neighbor link quality detection to work in case the packet
 549                 * originated from a single hop neighbor. Otherwise we can
 550                 * simply drop the ogm.
 551                 */
 552                if (is_single_hop_neigh)
 553                        batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP;
 554                else
 555                        return;
 556        }
 557
 558        tt_num_changes = batadv_ogm_packet->tt_num_changes;
 559
 560        batadv_ogm_packet->header.ttl--;
 561        memcpy(batadv_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 562
 563        /* apply hop penalty */
 564        batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq,
 565                                                   bat_priv);
 566
 567        batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 568                   "Forwarding packet: tq: %i, ttl: %i\n",
 569                   batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl);
 570
 571        /* switch of primaries first hop flag when forwarding */
 572        batadv_ogm_packet->flags &= ~BATADV_PRIMARIES_FIRST_HOP;
 573        if (is_single_hop_neigh)
 574                batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 575        else
 576                batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 577
 578        batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
 579                                BATADV_OGM_HLEN + batadv_tt_len(tt_num_changes),
 580                                if_incoming, 0, batadv_iv_ogm_fwd_send_time());
 581}
 582
 583static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
 584{
 585        struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 586        struct batadv_ogm_packet *batadv_ogm_packet;
 587        struct batadv_hard_iface *primary_if;
 588        int vis_server, tt_num_changes = 0;
 589
 590        vis_server = atomic_read(&bat_priv->vis_mode);
 591        primary_if = batadv_primary_if_get_selected(bat_priv);
 592
 593        if (hard_iface == primary_if)
 594                tt_num_changes = batadv_tt_append_diff(bat_priv,
 595                                                       &hard_iface->packet_buff,
 596                                                       &hard_iface->packet_len,
 597                                                       BATADV_OGM_HLEN);
 598
 599        batadv_ogm_packet = (struct batadv_ogm_packet *)hard_iface->packet_buff;
 600
 601        /* change sequence number to network order */
 602        batadv_ogm_packet->seqno =
 603                        htonl((uint32_t)atomic_read(&hard_iface->seqno));
 604        atomic_inc(&hard_iface->seqno);
 605
 606        batadv_ogm_packet->ttvn = atomic_read(&bat_priv->ttvn);
 607        batadv_ogm_packet->tt_crc = htons(bat_priv->tt_crc);
 608        if (tt_num_changes >= 0)
 609                batadv_ogm_packet->tt_num_changes = tt_num_changes;
 610
 611        if (vis_server == BATADV_VIS_TYPE_SERVER_SYNC)
 612                batadv_ogm_packet->flags |= BATADV_VIS_SERVER;
 613        else
 614                batadv_ogm_packet->flags &= ~BATADV_VIS_SERVER;
 615
 616        if ((hard_iface == primary_if) &&
 617            (atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_SERVER))
 618                batadv_ogm_packet->gw_flags =
 619                                (uint8_t)atomic_read(&bat_priv->gw_bandwidth);
 620        else
 621                batadv_ogm_packet->gw_flags = BATADV_NO_FLAGS;
 622
 623        batadv_slide_own_bcast_window(hard_iface);
 624        batadv_iv_ogm_queue_add(bat_priv, hard_iface->packet_buff,
 625                                hard_iface->packet_len, hard_iface, 1,
 626                                batadv_iv_ogm_emit_send_time(bat_priv));
 627
 628        if (primary_if)
 629                batadv_hardif_free_ref(primary_if);
 630}
 631
 632static void
 633batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv,
 634                          struct batadv_orig_node *orig_node,
 635                          const struct ethhdr *ethhdr,
 636                          const struct batadv_ogm_packet *batadv_ogm_packet,
 637                          struct batadv_hard_iface *if_incoming,
 638                          const unsigned char *tt_buff,
 639                          int is_duplicate)
 640{
 641        struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 642        struct batadv_neigh_node *router = NULL;
 643        struct batadv_orig_node *orig_node_tmp;
 644        struct hlist_node *node;
 645        int if_num;
 646        uint8_t sum_orig, sum_neigh;
 647        uint8_t *neigh_addr;
 648
 649        batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 650                   "update_originator(): Searching and updating originator entry of received packet\n");
 651
 652        rcu_read_lock();
 653        hlist_for_each_entry_rcu(tmp_neigh_node, node,
 654                                 &orig_node->neigh_list, list) {
 655                neigh_addr = tmp_neigh_node->addr;
 656                if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 657                    tmp_neigh_node->if_incoming == if_incoming &&
 658                    atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
 659                        if (neigh_node)
 660                                batadv_neigh_node_free_ref(neigh_node);
 661                        neigh_node = tmp_neigh_node;
 662                        continue;
 663                }
 664
 665                if (is_duplicate)
 666                        continue;
 667
 668                spin_lock_bh(&tmp_neigh_node->lq_update_lock);
 669                batadv_ring_buffer_set(tmp_neigh_node->tq_recv,
 670                                       &tmp_neigh_node->tq_index, 0);
 671                tmp_neigh_node->tq_avg =
 672                        batadv_ring_buffer_avg(tmp_neigh_node->tq_recv);
 673                spin_unlock_bh(&tmp_neigh_node->lq_update_lock);
 674        }
 675
 676        if (!neigh_node) {
 677                struct batadv_orig_node *orig_tmp;
 678
 679                orig_tmp = batadv_get_orig_node(bat_priv, ethhdr->h_source);
 680                if (!orig_tmp)
 681                        goto unlock;
 682
 683                neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 684                                                     ethhdr->h_source,
 685                                                     orig_node, orig_tmp,
 686                                                     batadv_ogm_packet->seqno);
 687
 688                batadv_orig_node_free_ref(orig_tmp);
 689                if (!neigh_node)
 690                        goto unlock;
 691        } else
 692                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 693                           "Updating existing last-hop neighbor of originator\n");
 694
 695        rcu_read_unlock();
 696
 697        orig_node->flags = batadv_ogm_packet->flags;
 698        neigh_node->last_seen = jiffies;
 699
 700        spin_lock_bh(&neigh_node->lq_update_lock);
 701        batadv_ring_buffer_set(neigh_node->tq_recv,
 702                               &neigh_node->tq_index,
 703                               batadv_ogm_packet->tq);
 704        neigh_node->tq_avg = batadv_ring_buffer_avg(neigh_node->tq_recv);
 705        spin_unlock_bh(&neigh_node->lq_update_lock);
 706
 707        if (!is_duplicate) {
 708                orig_node->last_ttl = batadv_ogm_packet->header.ttl;
 709                neigh_node->last_ttl = batadv_ogm_packet->header.ttl;
 710        }
 711
 712        batadv_bonding_candidate_add(orig_node, neigh_node);
 713
 714        /* if this neighbor already is our next hop there is nothing
 715         * to change
 716         */
 717        router = batadv_orig_node_get_router(orig_node);
 718        if (router == neigh_node)
 719                goto update_tt;
 720
 721        /* if this neighbor does not offer a better TQ we won't consider it */
 722        if (router && (router->tq_avg > neigh_node->tq_avg))
 723                goto update_tt;
 724
 725        /* if the TQ is the same and the link not more symmetric we
 726         * won't consider it either
 727         */
 728        if (router && (neigh_node->tq_avg == router->tq_avg)) {
 729                orig_node_tmp = router->orig_node;
 730                spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 731                if_num = router->if_incoming->if_num;
 732                sum_orig = orig_node_tmp->bcast_own_sum[if_num];
 733                spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 734
 735                orig_node_tmp = neigh_node->orig_node;
 736                spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 737                if_num = neigh_node->if_incoming->if_num;
 738                sum_neigh = orig_node_tmp->bcast_own_sum[if_num];
 739                spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 740
 741                if (sum_orig >= sum_neigh)
 742                        goto update_tt;
 743        }
 744
 745        batadv_update_route(bat_priv, orig_node, neigh_node);
 746
 747update_tt:
 748        /* I have to check for transtable changes only if the OGM has been
 749         * sent through a primary interface
 750         */
 751        if (((batadv_ogm_packet->orig != ethhdr->h_source) &&
 752             (batadv_ogm_packet->header.ttl > 2)) ||
 753            (batadv_ogm_packet->flags & BATADV_PRIMARIES_FIRST_HOP))
 754                batadv_tt_update_orig(bat_priv, orig_node, tt_buff,
 755                                      batadv_ogm_packet->tt_num_changes,
 756                                      batadv_ogm_packet->ttvn,
 757                                      ntohs(batadv_ogm_packet->tt_crc));
 758
 759        if (orig_node->gw_flags != batadv_ogm_packet->gw_flags)
 760                batadv_gw_node_update(bat_priv, orig_node,
 761                                      batadv_ogm_packet->gw_flags);
 762
 763        orig_node->gw_flags = batadv_ogm_packet->gw_flags;
 764
 765        /* restart gateway selection if fast or late switching was enabled */
 766        if ((orig_node->gw_flags) &&
 767            (atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_CLIENT) &&
 768            (atomic_read(&bat_priv->gw_sel_class) > 2))
 769                batadv_gw_check_election(bat_priv, orig_node);
 770
 771        goto out;
 772
 773unlock:
 774        rcu_read_unlock();
 775out:
 776        if (neigh_node)
 777                batadv_neigh_node_free_ref(neigh_node);
 778        if (router)
 779                batadv_neigh_node_free_ref(router);
 780}
 781
 782static int batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
 783                                 struct batadv_orig_node *orig_neigh_node,
 784                                 struct batadv_ogm_packet *batadv_ogm_packet,
 785                                 struct batadv_hard_iface *if_incoming)
 786{
 787        struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 788        struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node;
 789        struct hlist_node *node;
 790        uint8_t total_count;
 791        uint8_t orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
 792        unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
 793        int tq_asym_penalty, inv_asym_penalty, ret = 0;
 794        unsigned int combined_tq;
 795
 796        /* find corresponding one hop neighbor */
 797        rcu_read_lock();
 798        hlist_for_each_entry_rcu(tmp_neigh_node, node,
 799                                 &orig_neigh_node->neigh_list, list) {
 800
 801                if (!batadv_compare_eth(tmp_neigh_node->addr,
 802                                        orig_neigh_node->orig))
 803                        continue;
 804
 805                if (tmp_neigh_node->if_incoming != if_incoming)
 806                        continue;
 807
 808                if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 809                        continue;
 810
 811                neigh_node = tmp_neigh_node;
 812                break;
 813        }
 814        rcu_read_unlock();
 815
 816        if (!neigh_node)
 817                neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 818                                                     orig_neigh_node->orig,
 819                                                     orig_neigh_node,
 820                                                     orig_neigh_node,
 821                                                     batadv_ogm_packet->seqno);
 822
 823        if (!neigh_node)
 824                goto out;
 825
 826        /* if orig_node is direct neighbor update neigh_node last_seen */
 827        if (orig_node == orig_neigh_node)
 828                neigh_node->last_seen = jiffies;
 829
 830        orig_node->last_seen = jiffies;
 831
 832        /* find packet count of corresponding one hop neighbor */
 833        spin_lock_bh(&orig_node->ogm_cnt_lock);
 834        orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
 835        neigh_rq_count = neigh_node->real_packet_count;
 836        spin_unlock_bh(&orig_node->ogm_cnt_lock);
 837
 838        /* pay attention to not get a value bigger than 100 % */
 839        total_count = (orig_eq_count > neigh_rq_count ?
 840                       neigh_rq_count : orig_eq_count);
 841
 842        /* if we have too few packets (too less data) we set tq_own to zero
 843         * if we receive too few packets it is not considered bidirectional
 844         */
 845        if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
 846            neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
 847                tq_own = 0;
 848        else
 849                /* neigh_node->real_packet_count is never zero as we
 850                 * only purge old information when getting new
 851                 * information
 852                 */
 853                tq_own = (BATADV_TQ_MAX_VALUE * total_count) /  neigh_rq_count;
 854
 855        /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 856         * affect the nearly-symmetric links only a little, but
 857         * punishes asymmetric links more.  This will give a value
 858         * between 0 and TQ_MAX_VALUE
 859         */
 860        neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
 861        neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
 862        neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
 863                            BATADV_TQ_LOCAL_WINDOW_SIZE *
 864                            BATADV_TQ_LOCAL_WINDOW_SIZE;
 865        inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
 866        inv_asym_penalty /= neigh_rq_max_cube;
 867        tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;
 868
 869        combined_tq = batadv_ogm_packet->tq * tq_own * tq_asym_penalty;
 870        combined_tq /= BATADV_TQ_MAX_VALUE * BATADV_TQ_MAX_VALUE;
 871        batadv_ogm_packet->tq = combined_tq;
 872
 873        batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 874                   "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n",
 875                   orig_node->orig, orig_neigh_node->orig, total_count,
 876                   neigh_rq_count, tq_own,
 877                   tq_asym_penalty, batadv_ogm_packet->tq);
 878
 879        /* if link has the minimum required transmission quality
 880         * consider it bidirectional
 881         */
 882        if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
 883                ret = 1;
 884
 885out:
 886        if (neigh_node)
 887                batadv_neigh_node_free_ref(neigh_node);
 888        return ret;
 889}
 890
 891/* processes a batman packet for all interfaces, adjusts the sequence number and
 892 * finds out whether it is a duplicate.
 893 * returns:
 894 *   1 the packet is a duplicate
 895 *   0 the packet has not yet been received
 896 *  -1 the packet is old and has been received while the seqno window
 897 *     was protected. Caller should drop it.
 898 */
 899static int
 900batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
 901                            const struct batadv_ogm_packet *batadv_ogm_packet,
 902                            const struct batadv_hard_iface *if_incoming)
 903{
 904        struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 905        struct batadv_orig_node *orig_node;
 906        struct batadv_neigh_node *tmp_neigh_node;
 907        struct hlist_node *node;
 908        int is_duplicate = 0;
 909        int32_t seq_diff;
 910        int need_update = 0;
 911        int set_mark, ret = -1;
 912        uint32_t seqno = ntohl(batadv_ogm_packet->seqno);
 913        uint8_t *neigh_addr;
 914
 915        orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig);
 916        if (!orig_node)
 917                return 0;
 918
 919        spin_lock_bh(&orig_node->ogm_cnt_lock);
 920        seq_diff = seqno - orig_node->last_real_seqno;
 921
 922        /* signalize caller that the packet is to be dropped. */
 923        if (!hlist_empty(&orig_node->neigh_list) &&
 924            batadv_window_protected(bat_priv, seq_diff,
 925                                    &orig_node->batman_seqno_reset))
 926                goto out;
 927
 928        rcu_read_lock();
 929        hlist_for_each_entry_rcu(tmp_neigh_node, node,
 930                                 &orig_node->neigh_list, list) {
 931
 932                is_duplicate |= batadv_test_bit(tmp_neigh_node->real_bits,
 933                                                orig_node->last_real_seqno,
 934                                                seqno);
 935
 936                neigh_addr = tmp_neigh_node->addr;
 937                if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 938                    tmp_neigh_node->if_incoming == if_incoming)
 939                        set_mark = 1;
 940                else
 941                        set_mark = 0;
 942
 943                /* if the window moved, set the update flag. */
 944                need_update |= batadv_bit_get_packet(bat_priv,
 945                                                     tmp_neigh_node->real_bits,
 946                                                     seq_diff, set_mark);
 947
 948                tmp_neigh_node->real_packet_count =
 949                        bitmap_weight(tmp_neigh_node->real_bits,
 950                                      BATADV_TQ_LOCAL_WINDOW_SIZE);
 951        }
 952        rcu_read_unlock();
 953
 954        if (need_update) {
 955                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 956                           "updating last_seqno: old %u, new %u\n",
 957                           orig_node->last_real_seqno, seqno);
 958                orig_node->last_real_seqno = seqno;
 959        }
 960
 961        ret = is_duplicate;
 962
 963out:
 964        spin_unlock_bh(&orig_node->ogm_cnt_lock);
 965        batadv_orig_node_free_ref(orig_node);
 966        return ret;
 967}
 968
 969static void batadv_iv_ogm_process(const struct ethhdr *ethhdr,
 970                                  struct batadv_ogm_packet *batadv_ogm_packet,
 971                                  const unsigned char *tt_buff,
 972                                  struct batadv_hard_iface *if_incoming)
 973{
 974        struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 975        struct batadv_hard_iface *hard_iface;
 976        struct batadv_orig_node *orig_neigh_node, *orig_node;
 977        struct batadv_neigh_node *router = NULL, *router_router = NULL;
 978        struct batadv_neigh_node *orig_neigh_router = NULL;
 979        int has_directlink_flag;
 980        int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
 981        int is_broadcast = 0, is_bidirect;
 982        bool is_single_hop_neigh = false;
 983        bool is_from_best_next_hop = false;
 984        int is_duplicate, sameseq, simlar_ttl;
 985        uint32_t if_incoming_seqno;
 986        uint8_t *prev_sender;
 987
 988        /* Silently drop when the batman packet is actually not a
 989         * correct packet.
 990         *
 991         * This might happen if a packet is padded (e.g. Ethernet has a
 992         * minimum frame length of 64 byte) and the aggregation interprets
 993         * it as an additional length.
 994         *
 995         * TODO: A more sane solution would be to have a bit in the
 996         * batadv_ogm_packet to detect whether the packet is the last
 997         * packet in an aggregation.  Here we expect that the padding
 998         * is always zero (or not 0x01)
 999         */
1000        if (batadv_ogm_packet->header.packet_type != BATADV_IV_OGM)
1001                return;
1002
1003        /* could be changed by schedule_own_packet() */
1004        if_incoming_seqno = atomic_read(&if_incoming->seqno);
1005
1006        if (batadv_ogm_packet->flags & BATADV_DIRECTLINK)
1007                has_directlink_flag = 1;
1008        else
1009                has_directlink_flag = 0;
1010
1011        if (batadv_compare_eth(ethhdr->h_source, batadv_ogm_packet->orig))
1012                is_single_hop_neigh = true;
1013
1014        batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1015                   "Received BATMAN packet via NB: %pM, IF: %s [%pM] (from OG: %pM, via prev OG: %pM, seqno %u, ttvn %u, crc %u, changes %u, td %d, TTL %d, V %d, IDF %d)\n",
1016                   ethhdr->h_source, if_incoming->net_dev->name,
1017                   if_incoming->net_dev->dev_addr, batadv_ogm_packet->orig,
1018                   batadv_ogm_packet->prev_sender,
1019                   ntohl(batadv_ogm_packet->seqno), batadv_ogm_packet->ttvn,
1020                   ntohs(batadv_ogm_packet->tt_crc),
1021                   batadv_ogm_packet->tt_num_changes, batadv_ogm_packet->tq,
1022                   batadv_ogm_packet->header.ttl,
1023                   batadv_ogm_packet->header.version, has_directlink_flag);
1024
1025        rcu_read_lock();
1026        list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1027                if (hard_iface->if_status != BATADV_IF_ACTIVE)
1028                        continue;
1029
1030                if (hard_iface->soft_iface != if_incoming->soft_iface)
1031                        continue;
1032
1033                if (batadv_compare_eth(ethhdr->h_source,
1034                                       hard_iface->net_dev->dev_addr))
1035                        is_my_addr = 1;
1036
1037                if (batadv_compare_eth(batadv_ogm_packet->orig,
1038                                       hard_iface->net_dev->dev_addr))
1039                        is_my_orig = 1;
1040
1041                if (batadv_compare_eth(batadv_ogm_packet->prev_sender,
1042                                       hard_iface->net_dev->dev_addr))
1043                        is_my_oldorig = 1;
1044
1045                if (is_broadcast_ether_addr(ethhdr->h_source))
1046                        is_broadcast = 1;
1047        }
1048        rcu_read_unlock();
1049
1050        if (batadv_ogm_packet->header.version != BATADV_COMPAT_VERSION) {
1051                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1052                           "Drop packet: incompatible batman version (%i)\n",
1053                           batadv_ogm_packet->header.version);
1054                return;
1055        }
1056
1057        if (is_my_addr) {
1058                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1059                           "Drop packet: received my own broadcast (sender: %pM)\n",
1060                           ethhdr->h_source);
1061                return;
1062        }
1063
1064        if (is_broadcast) {
1065                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1066                           "Drop packet: ignoring all packets with broadcast source addr (sender: %pM)\n",
1067                           ethhdr->h_source);
1068                return;
1069        }
1070
1071        if (is_my_orig) {
1072                unsigned long *word;
1073                int offset;
1074                int32_t bit_pos;
1075                int16_t if_num;
1076                uint8_t *weight;
1077
1078                orig_neigh_node = batadv_get_orig_node(bat_priv,
1079                                                       ethhdr->h_source);
1080                if (!orig_neigh_node)
1081                        return;
1082
1083                /* neighbor has to indicate direct link and it has to
1084                 * come via the corresponding interface
1085                 * save packet seqno for bidirectional check
1086                 */
1087                if (has_directlink_flag &&
1088                    batadv_compare_eth(if_incoming->net_dev->dev_addr,
1089                                       batadv_ogm_packet->orig)) {
1090                        if_num = if_incoming->if_num;
1091                        offset = if_num * BATADV_NUM_WORDS;
1092
1093                        spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
1094                        word = &(orig_neigh_node->bcast_own[offset]);
1095                        bit_pos = if_incoming_seqno - 2;
1096                        bit_pos -= ntohl(batadv_ogm_packet->seqno);
1097                        batadv_set_bit(word, bit_pos);
1098                        weight = &orig_neigh_node->bcast_own_sum[if_num];
1099                        *weight = bitmap_weight(word,
1100                                                BATADV_TQ_LOCAL_WINDOW_SIZE);
1101                        spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
1102                }
1103
1104                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1105                           "Drop packet: originator packet from myself (via neighbor)\n");
1106                batadv_orig_node_free_ref(orig_neigh_node);
1107                return;
1108        }
1109
1110        if (is_my_oldorig) {
1111                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1112                           "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1113                           ethhdr->h_source);
1114                return;
1115        }
1116
1117        if (batadv_ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) {
1118                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1119                           "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1120                           ethhdr->h_source);
1121                return;
1122        }
1123
1124        orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig);
1125        if (!orig_node)
1126                return;
1127
1128        is_duplicate = batadv_iv_ogm_update_seqnos(ethhdr, batadv_ogm_packet,
1129                                                   if_incoming);
1130
1131        if (is_duplicate == -1) {
1132                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1133                           "Drop packet: packet within seqno protection time (sender: %pM)\n",
1134                           ethhdr->h_source);
1135                goto out;
1136        }
1137
1138        if (batadv_ogm_packet->tq == 0) {
1139                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1140                           "Drop packet: originator packet with tq equal 0\n");
1141                goto out;
1142        }
1143
1144        router = batadv_orig_node_get_router(orig_node);
1145        if (router)
1146                router_router = batadv_orig_node_get_router(router->orig_node);
1147
1148        if ((router && router->tq_avg != 0) &&
1149            (batadv_compare_eth(router->addr, ethhdr->h_source)))
1150                is_from_best_next_hop = true;
1151
1152        prev_sender = batadv_ogm_packet->prev_sender;
1153        /* avoid temporary routing loops */
1154        if (router && router_router &&
1155            (batadv_compare_eth(router->addr, prev_sender)) &&
1156            !(batadv_compare_eth(batadv_ogm_packet->orig, prev_sender)) &&
1157            (batadv_compare_eth(router->addr, router_router->addr))) {
1158                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1159                           "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1160                           ethhdr->h_source);
1161                goto out;
1162        }
1163
1164        /* if sender is a direct neighbor the sender mac equals
1165         * originator mac
1166         */
1167        orig_neigh_node = (is_single_hop_neigh ?
1168                           orig_node :
1169                           batadv_get_orig_node(bat_priv, ethhdr->h_source));
1170        if (!orig_neigh_node)
1171                goto out;
1172
1173        orig_neigh_router = batadv_orig_node_get_router(orig_neigh_node);
1174
1175        /* drop packet if sender is not a direct neighbor and if we
1176         * don't route towards it
1177         */
1178        if (!is_single_hop_neigh && (!orig_neigh_router)) {
1179                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1180                           "Drop packet: OGM via unknown neighbor!\n");
1181                goto out_neigh;
1182        }
1183
1184        is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1185                                            batadv_ogm_packet, if_incoming);
1186
1187        batadv_bonding_save_primary(orig_node, orig_neigh_node,
1188                                    batadv_ogm_packet);
1189
1190        /* update ranking if it is not a duplicate or has the same
1191         * seqno and similar ttl as the non-duplicate
1192         */
1193        sameseq = orig_node->last_real_seqno == ntohl(batadv_ogm_packet->seqno);
1194        simlar_ttl = orig_node->last_ttl - 3 <= batadv_ogm_packet->header.ttl;
1195        if (is_bidirect && (!is_duplicate || (sameseq && simlar_ttl)))
1196                batadv_iv_ogm_orig_update(bat_priv, orig_node, ethhdr,
1197                                          batadv_ogm_packet, if_incoming,
1198                                          tt_buff, is_duplicate);
1199
1200        /* is single hop (direct) neighbor */
1201        if (is_single_hop_neigh) {
1202
1203                /* mark direct link on incoming interface */
1204                batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1205                                      is_single_hop_neigh,
1206                                      is_from_best_next_hop, if_incoming);
1207
1208                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1209                           "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1210                goto out_neigh;
1211        }
1212
1213        /* multihop originator */
1214        if (!is_bidirect) {
1215                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1216                           "Drop packet: not received via bidirectional link\n");
1217                goto out_neigh;
1218        }
1219
1220        if (is_duplicate) {
1221                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1222                           "Drop packet: duplicate packet received\n");
1223                goto out_neigh;
1224        }
1225
1226        batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1227                   "Forwarding packet: rebroadcast originator packet\n");
1228        batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1229                              is_single_hop_neigh, is_from_best_next_hop,
1230                              if_incoming);
1231
1232out_neigh:
1233        if ((orig_neigh_node) && (!is_single_hop_neigh))
1234                batadv_orig_node_free_ref(orig_neigh_node);
1235out:
1236        if (router)
1237                batadv_neigh_node_free_ref(router);
1238        if (router_router)
1239                batadv_neigh_node_free_ref(router_router);
1240        if (orig_neigh_router)
1241                batadv_neigh_node_free_ref(orig_neigh_router);
1242
1243        batadv_orig_node_free_ref(orig_node);
1244}
1245
1246static int batadv_iv_ogm_receive(struct sk_buff *skb,
1247                                 struct batadv_hard_iface *if_incoming)
1248{
1249        struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1250        struct batadv_ogm_packet *batadv_ogm_packet;
1251        struct ethhdr *ethhdr;
1252        int buff_pos = 0, packet_len;
1253        unsigned char *tt_buff, *packet_buff;
1254        bool ret;
1255
1256        ret = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
1257        if (!ret)
1258                return NET_RX_DROP;
1259
1260        /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1261         * that does not have B.A.T.M.A.N. IV enabled ?
1262         */
1263        if (bat_priv->bat_algo_ops->bat_ogm_emit != batadv_iv_ogm_emit)
1264                return NET_RX_DROP;
1265
1266        batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
1267        batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
1268                           skb->len + ETH_HLEN);
1269
1270        packet_len = skb_headlen(skb);
1271        ethhdr = (struct ethhdr *)skb_mac_header(skb);
1272        packet_buff = skb->data;
1273        batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
1274
1275        /* unpack the aggregated packets and process them one by one */
1276        do {
1277                tt_buff = packet_buff + buff_pos + BATADV_OGM_HLEN;
1278
1279                batadv_iv_ogm_process(ethhdr, batadv_ogm_packet, tt_buff,
1280                                      if_incoming);
1281
1282                buff_pos += BATADV_OGM_HLEN;
1283                buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
1284
1285                batadv_ogm_packet = (struct batadv_ogm_packet *)
1286                                                (packet_buff + buff_pos);
1287        } while (batadv_iv_ogm_aggr_packet(buff_pos, packet_len,
1288                                           batadv_ogm_packet->tt_num_changes));
1289
1290        kfree_skb(skb);
1291        return NET_RX_SUCCESS;
1292}
1293
1294static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
1295        .name = "BATMAN_IV",
1296        .bat_iface_enable = batadv_iv_ogm_iface_enable,
1297        .bat_iface_disable = batadv_iv_ogm_iface_disable,
1298        .bat_iface_update_mac = batadv_iv_ogm_iface_update_mac,
1299        .bat_primary_iface_set = batadv_iv_ogm_primary_iface_set,
1300        .bat_ogm_schedule = batadv_iv_ogm_schedule,
1301        .bat_ogm_emit = batadv_iv_ogm_emit,
1302};
1303
1304int __init batadv_iv_init(void)
1305{
1306        int ret;
1307
1308        /* batman originator packet */
1309        ret = batadv_recv_handler_register(BATADV_IV_OGM,
1310                                           batadv_iv_ogm_receive);
1311        if (ret < 0)
1312                goto out;
1313
1314        ret = batadv_algo_register(&batadv_batman_iv);
1315        if (ret < 0)
1316                goto handler_unregister;
1317
1318        goto out;
1319
1320handler_unregister:
1321        batadv_recv_handler_unregister(BATADV_IV_OGM);
1322out:
1323        return ret;
1324}
1325
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