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 "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 #include "network-coding.h"
  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 static struct batadv_neigh_node *
  48 batadv_iv_ogm_neigh_new(struct batadv_hard_iface *hard_iface,
  49                         const uint8_t *neigh_addr,
  50                         struct batadv_orig_node *orig_node,
  51                         struct batadv_orig_node *orig_neigh, __be32 seqno)
  52 {
  53         struct batadv_neigh_node *neigh_node;
  54
  55         neigh_node = batadv_neigh_node_new(hard_iface, neigh_addr,
  56                                            ntohl(seqno));
  57         if (!neigh_node)
  58                 goto out;
  59
  60         INIT_LIST_HEAD(&neigh_node->bonding_list);
  61
  62         neigh_node->orig_node = orig_neigh;
  63         neigh_node->if_incoming = hard_iface;
  64
  65         spin_lock_bh(&orig_node->neigh_list_lock);
  66         hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list);
  67         spin_unlock_bh(&orig_node->neigh_list_lock);
  68
  69 out:
  70         return neigh_node;
  71 }
  72
  73 static int batadv_iv_ogm_iface_enable(struct batadv_hard_iface *hard_iface)
  74 {
  75         struct batadv_ogm_packet *batadv_ogm_packet;
  76         unsigned char *ogm_buff;
  77         uint32_t random_seqno;
  78         int res = -ENOMEM;
  79
  80         /* randomize initial seqno to avoid collision */
  81         get_random_bytes(&random_seqno, sizeof(random_seqno));
  82         atomic_set(&hard_iface->bat_iv.ogm_seqno, random_seqno);
  83
  84         hard_iface->bat_iv.ogm_buff_len = BATADV_OGM_HLEN;
  85         ogm_buff = kmalloc(hard_iface->bat_iv.ogm_buff_len, GFP_ATOMIC);
  86         if (!ogm_buff)
  87                 goto out;
  88
  89         hard_iface->bat_iv.ogm_buff = ogm_buff;
  90
  91         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
  92         batadv_ogm_packet->header.packet_type = BATADV_IV_OGM;
  93         batadv_ogm_packet->header.version = BATADV_COMPAT_VERSION;
  94         batadv_ogm_packet->header.ttl = 2;
  95         batadv_ogm_packet->flags = BATADV_NO_FLAGS;
  96         batadv_ogm_packet->tq = BATADV_TQ_MAX_VALUE;
  97         batadv_ogm_packet->tt_num_changes = 0;
  98         batadv_ogm_packet->ttvn = 0;
  99
 100         res = 0;
 101
 102 out:
 103         return res;
 104 }
 105
 106 static void batadv_iv_ogm_iface_disable(struct batadv_hard_iface *hard_iface)
 107 {
 108         kfree(hard_iface->bat_iv.ogm_buff);
 109         hard_iface->bat_iv.ogm_buff = NULL;
 110 }
 111
 112 static void batadv_iv_ogm_iface_update_mac(struct batadv_hard_iface *hard_iface)
 113 {
 114         struct batadv_ogm_packet *batadv_ogm_packet;
 115         unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
 116
 117         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 118         memcpy(batadv_ogm_packet->orig,
 119                hard_iface->net_dev->dev_addr, ETH_ALEN);
 120         memcpy(batadv_ogm_packet->prev_sender,
 121                hard_iface->net_dev->dev_addr, ETH_ALEN);
 122 }
 123
 124 static void
 125 batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface)
 126 {
 127         struct batadv_ogm_packet *batadv_ogm_packet;
 128         unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
 129
 130         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 131         batadv_ogm_packet->flags = BATADV_PRIMARIES_FIRST_HOP;
 132         batadv_ogm_packet->header.ttl = BATADV_TTL;
 133 }
 134
 135 /* when do we schedule our own ogm to be sent */
 136 static unsigned long
 137 batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
 138 {
 139         unsigned int msecs;
 140
 141         msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
 142         msecs += prandom_u32() % (2 * BATADV_JITTER);
 143
 144         return jiffies + msecs_to_jiffies(msecs);
 145 }
 146
 147 /* when do we schedule a ogm packet to be sent */
 148 static unsigned long batadv_iv_ogm_fwd_send_time(void)
 149 {
 150         return jiffies + msecs_to_jiffies(prandom_u32() % (BATADV_JITTER / 2));
 151 }
 152
 153 /* apply hop penalty for a normal link */
 154 static uint8_t batadv_hop_penalty(uint8_t tq,
 155                                   const struct batadv_priv *bat_priv)
 156 {
 157         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
 158         int new_tq;
 159
 160         new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty);
 161         new_tq /= BATADV_TQ_MAX_VALUE;
 162
 163         return new_tq;
 164 }
 165
 166 /* is there another aggregated packet here? */
 167 static int batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
 168                                      int tt_num_changes)
 169 {
 170         int next_buff_pos = 0;
 171
 172         next_buff_pos += buff_pos + BATADV_OGM_HLEN;
 173         next_buff_pos += batadv_tt_len(tt_num_changes);
 174
 175         return (next_buff_pos <= packet_len) &&
 176                (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
 177 }
 178
 179 /* send a batman ogm to a given interface */
 180 static void batadv_iv_ogm_send_to_if(struct batadv_forw_packet *forw_packet,
 181                                      struct batadv_hard_iface *hard_iface)
 182 {
 183         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 184         char *fwd_str;
 185         uint8_t packet_num;
 186         int16_t buff_pos;
 187         struct batadv_ogm_packet *batadv_ogm_packet;
 188         struct sk_buff *skb;
 189         uint8_t *packet_pos;
 190
 191         if (hard_iface->if_status != BATADV_IF_ACTIVE)
 192                 return;
 193
 194         packet_num = 0;
 195         buff_pos = 0;
 196         packet_pos = forw_packet->skb->data;
 197         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 198
 199         /* adjust all flags and log packets */
 200         while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
 201                                          batadv_ogm_packet->tt_num_changes)) {
 202                 /* we might have aggregated direct link packets with an
 203                  * ordinary base packet
 204                  */
 205                 if (forw_packet->direct_link_flags & BIT(packet_num) &&
 206                     forw_packet->if_incoming == hard_iface)
 207                         batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 208                 else
 209                         batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 210
 211                 if (packet_num > 0 || !forw_packet->own)
 212                         fwd_str = "Forwarding";
 213                 else
 214                         fwd_str = "Sending own";
 215
 216                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 217                            "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s, ttvn %d) on interface %s [%pM]\n",
 218                            fwd_str, (packet_num > 0 ? "aggregated " : ""),
 219                            batadv_ogm_packet->orig,
 220                            ntohl(batadv_ogm_packet->seqno),
 221                            batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl,
 222                            (batadv_ogm_packet->flags & BATADV_DIRECTLINK ?
 223                             "on" : "off"),
 224                            batadv_ogm_packet->ttvn, hard_iface->net_dev->name,
 225                            hard_iface->net_dev->dev_addr);
 226
 227                 buff_pos += BATADV_OGM_HLEN;
 228                 buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
 229                 packet_num++;
 230                 packet_pos = forw_packet->skb->data + buff_pos;
 231                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 232         }
 233
 234         /* create clone because function is called more than once */
 235         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
 236         if (skb) {
 237                 batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
 238                 batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
 239                                    skb->len + ETH_HLEN);
 240                 batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
 241         }
 242 }
 243
 244 /* send a batman ogm packet */
 245 static void batadv_iv_ogm_emit(struct batadv_forw_packet *forw_packet)
 246 {
 247         struct batadv_hard_iface *hard_iface;
 248         struct net_device *soft_iface;
 249         struct batadv_priv *bat_priv;
 250         struct batadv_hard_iface *primary_if = NULL;
 251         struct batadv_ogm_packet *batadv_ogm_packet;
 252         unsigned char directlink;
 253         uint8_t *packet_pos;
 254
 255         packet_pos = forw_packet->skb->data;
 256         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 257         directlink = (batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0);
 258
 259         if (!forw_packet->if_incoming) {
 260                 pr_err("Error - can't forward packet: incoming iface not specified\n");
 261                 goto out;
 262         }
 263
 264         soft_iface = forw_packet->if_incoming->soft_iface;
 265         bat_priv = netdev_priv(soft_iface);
 266
 267         if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE)
 268                 goto out;
 269
 270         primary_if = batadv_primary_if_get_selected(bat_priv);
 271         if (!primary_if)
 272                 goto out;
 273
 274         /* multihomed peer assumed
 275          * non-primary OGMs are only broadcasted on their interface
 276          */
 277         if ((directlink && (batadv_ogm_packet->header.ttl == 1)) ||
 278             (forw_packet->own && (forw_packet->if_incoming != primary_if))) {
 279                 /* FIXME: what about aggregated packets ? */
 280                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 281                            "%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n",
 282                            (forw_packet->own ? "Sending own" : "Forwarding"),
 283                            batadv_ogm_packet->orig,
 284                            ntohl(batadv_ogm_packet->seqno),
 285                            batadv_ogm_packet->header.ttl,
 286                            forw_packet->if_incoming->net_dev->name,
 287                            forw_packet->if_incoming->net_dev->dev_addr);
 288
 289                 /* skb is only used once and than forw_packet is free'd */
 290                 batadv_send_skb_packet(forw_packet->skb,
 291                                        forw_packet->if_incoming,
 292                                        batadv_broadcast_addr);
 293                 forw_packet->skb = NULL;
 294
 295                 goto out;
 296         }
 297
 298         /* broadcast on every interface */
 299         rcu_read_lock();
 300         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 301                 if (hard_iface->soft_iface != soft_iface)
 302                         continue;
 303
 304                 batadv_iv_ogm_send_to_if(forw_packet, hard_iface);
 305         }
 306         rcu_read_unlock();
 307
 308 out:
 309         if (primary_if)
 310                 batadv_hardif_free_ref(primary_if);
 311 }
 312
 313 /* return true if new_packet can be aggregated with forw_packet */
 314 static bool
 315 batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet,
 316                             struct batadv_priv *bat_priv,
 317                             int packet_len, unsigned long send_time,
 318                             bool directlink,
 319                             const struct batadv_hard_iface *if_incoming,
 320                             const struct batadv_forw_packet *forw_packet)
 321 {
 322         struct batadv_ogm_packet *batadv_ogm_packet;
 323         int aggregated_bytes = forw_packet->packet_len + packet_len;
 324         struct batadv_hard_iface *primary_if = NULL;
 325         bool res = false;
 326         unsigned long aggregation_end_time;
 327
 328         batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
 329         aggregation_end_time = send_time;
 330         aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 331
 332         /* we can aggregate the current packet to this aggregated packet
 333          * if:
 334          *
 335          * - the send time is within our MAX_AGGREGATION_MS time
 336          * - the resulting packet wont be bigger than
 337          *   MAX_AGGREGATION_BYTES
 338          */
 339         if (time_before(send_time, forw_packet->send_time) &&
 340             time_after_eq(aggregation_end_time, forw_packet->send_time) &&
 341             (aggregated_bytes <= BATADV_MAX_AGGREGATION_BYTES)) {
 342                 /* check aggregation compatibility
 343                  * -> direct link packets are broadcasted on
 344                  *    their interface only
 345                  * -> aggregate packet if the current packet is
 346                  *    a "global" packet as well as the base
 347                  *    packet
 348                  */
 349                 primary_if = batadv_primary_if_get_selected(bat_priv);
 350                 if (!primary_if)
 351                         goto out;
 352
 353                 /* packets without direct link flag and high TTL
 354                  * are flooded through the net
 355                  */
 356                 if ((!directlink) &&
 357                     (!(batadv_ogm_packet->flags & BATADV_DIRECTLINK)) &&
 358                     (batadv_ogm_packet->header.ttl != 1) &&
 359
 360                     /* own packets originating non-primary
 361                      * interfaces leave only that interface
 362                      */
 363                     ((!forw_packet->own) ||
 364                      (forw_packet->if_incoming == primary_if))) {
 365                         res = true;
 366                         goto out;
 367                 }
 368
 369                 /* if the incoming packet is sent via this one
 370                  * interface only - we still can aggregate
 371                  */
 372                 if ((directlink) &&
 373                     (new_bat_ogm_packet->header.ttl == 1) &&
 374                     (forw_packet->if_incoming == if_incoming) &&
 375
 376                     /* packets from direct neighbors or
 377                      * own secondary interface packets
 378                      * (= secondary interface packets in general)
 379                      */
 380                     (batadv_ogm_packet->flags & BATADV_DIRECTLINK ||
 381                      (forw_packet->own &&
 382                       forw_packet->if_incoming != primary_if))) {
 383                         res = true;
 384                         goto out;
 385                 }
 386         }
 387
 388 out:
 389         if (primary_if)
 390                 batadv_hardif_free_ref(primary_if);
 391         return res;
 392 }
 393
 394 /* create a new aggregated packet and add this packet to it */
 395 static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 396                                         int packet_len, unsigned long send_time,
 397                                         bool direct_link,
 398                                         struct batadv_hard_iface *if_incoming,
 399                                         int own_packet)
 400 {
 401         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 402         struct batadv_forw_packet *forw_packet_aggr;
 403         unsigned char *skb_buff;
 404         unsigned int skb_size;
 405
 406         if (!atomic_inc_not_zero(&if_incoming->refcount))
 407                 return;
 408
 409         /* own packet should always be scheduled */
 410         if (!own_packet) {
 411                 if (!batadv_atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
 412                         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 413                                    "batman packet queue full\n");
 414                         goto out;
 415                 }
 416         }
 417
 418         forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
 419         if (!forw_packet_aggr) {
 420                 if (!own_packet)
 421                         atomic_inc(&bat_priv->batman_queue_left);
 422                 goto out;
 423         }
 424
 425         if ((atomic_read(&bat_priv->aggregated_ogms)) &&
 426             (packet_len < BATADV_MAX_AGGREGATION_BYTES))
 427                 skb_size = BATADV_MAX_AGGREGATION_BYTES;
 428         else
 429                 skb_size = packet_len;
 430
 431         skb_size += ETH_HLEN + NET_IP_ALIGN;
 432
 433         forw_packet_aggr->skb = dev_alloc_skb(skb_size);
 434         if (!forw_packet_aggr->skb) {
 435                 if (!own_packet)
 436                         atomic_inc(&bat_priv->batman_queue_left);
 437                 kfree(forw_packet_aggr);
 438                 goto out;
 439         }
 440         skb_reserve(forw_packet_aggr->skb, ETH_HLEN + NET_IP_ALIGN);
 441
 442         INIT_HLIST_NODE(&forw_packet_aggr->list);
 443
 444         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 445         forw_packet_aggr->packet_len = packet_len;
 446         memcpy(skb_buff, packet_buff, packet_len);
 447
 448         forw_packet_aggr->own = own_packet;
 449         forw_packet_aggr->if_incoming = if_incoming;
 450         forw_packet_aggr->num_packets = 0;
 451         forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
 452         forw_packet_aggr->send_time = send_time;
 453
 454         /* save packet direct link flag status */
 455         if (direct_link)
 456                 forw_packet_aggr->direct_link_flags |= 1;
 457
 458         /* add new packet to packet list */
 459         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 460         hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
 461         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 462
 463         /* start timer for this packet */
 464         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 465                           batadv_send_outstanding_bat_ogm_packet);
 466         queue_delayed_work(batadv_event_workqueue,
 467                            &forw_packet_aggr->delayed_work,
 468                            send_time - jiffies);
 469
 470         return;
 471 out:
 472         batadv_hardif_free_ref(if_incoming);
 473 }
 474
 475 /* aggregate a new packet into the existing ogm packet */
 476 static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr,
 477                                     const unsigned char *packet_buff,
 478                                     int packet_len, bool direct_link)
 479 {
 480         unsigned char *skb_buff;
 481         unsigned long new_direct_link_flag;
 482
 483         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 484         memcpy(skb_buff, packet_buff, packet_len);
 485         forw_packet_aggr->packet_len += packet_len;
 486         forw_packet_aggr->num_packets++;
 487
 488         /* save packet direct link flag status */
 489         if (direct_link) {
 490                 new_direct_link_flag = BIT(forw_packet_aggr->num_packets);
 491                 forw_packet_aggr->direct_link_flags |= new_direct_link_flag;
 492         }
 493 }
 494
 495 static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv,
 496                                     unsigned char *packet_buff,
 497                                     int packet_len,
 498                                     struct batadv_hard_iface *if_incoming,
 499                                     int own_packet, unsigned long send_time)
 500 {
 501         /* _aggr -> pointer to the packet we want to aggregate with
 502          * _pos -> pointer to the position in the queue
 503          */
 504         struct batadv_forw_packet *forw_packet_aggr = NULL;
 505         struct batadv_forw_packet *forw_packet_pos = NULL;
 506         struct batadv_ogm_packet *batadv_ogm_packet;
 507         bool direct_link;
 508         unsigned long max_aggregation_jiffies;
 509
 510         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
 511         direct_link = batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0;
 512         max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 513
 514         /* find position for the packet in the forward queue */
 515         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 516         /* own packets are not to be aggregated */
 517         if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
 518                 hlist_for_each_entry(forw_packet_pos,
 519                                      &bat_priv->forw_bat_list, list) {
 520                         if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet,
 521                                                         bat_priv, packet_len,
 522                                                         send_time, direct_link,
 523                                                         if_incoming,
 524                                                         forw_packet_pos)) {
 525                                 forw_packet_aggr = forw_packet_pos;
 526                                 break;
 527                         }
 528                 }
 529         }
 530
 531         /* nothing to aggregate with - either aggregation disabled or no
 532          * suitable aggregation packet found
 533          */
 534         if (!forw_packet_aggr) {
 535                 /* the following section can run without the lock */
 536                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 537
 538                 /* if we could not aggregate this packet with one of the others
 539                  * we hold it back for a while, so that it might be aggregated
 540                  * later on
 541                  */
 542                 if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
 543                         send_time += max_aggregation_jiffies;
 544
 545                 batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
 546                                             send_time, direct_link,
 547                                             if_incoming, own_packet);
 548         } else {
 549                 batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 550                                         packet_len, direct_link);
 551                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 552         }
 553 }
 554
 555 static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
 556                                   const struct ethhdr *ethhdr,
 557                                   struct batadv_ogm_packet *batadv_ogm_packet,
 558                                   bool is_single_hop_neigh,
 559                                   bool is_from_best_next_hop,
 560                                   struct batadv_hard_iface *if_incoming)
 561 {
 562         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 563         uint8_t tt_num_changes;
 564
 565         if (batadv_ogm_packet->header.ttl <= 1) {
 566                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
 567                 return;
 568         }
 569
 570         if (!is_from_best_next_hop) {
 571                 /* Mark the forwarded packet when it is not coming from our
 572                  * best next hop. We still need to forward the packet for our
 573                  * neighbor link quality detection to work in case the packet
 574                  * originated from a single hop neighbor. Otherwise we can
 575                  * simply drop the ogm.
 576                  */
 577                 if (is_single_hop_neigh)
 578                         batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP;
 579                 else
 580                         return;
 581         }
 582
 583         tt_num_changes = batadv_ogm_packet->tt_num_changes;
 584
 585         batadv_ogm_packet->header.ttl--;
 586         memcpy(batadv_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 587
 588         /* apply hop penalty */
 589         batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq,
 590                                                    bat_priv);
 591
 592         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 593                    "Forwarding packet: tq: %i, ttl: %i\n",
 594                    batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl);
 595
 596         /* switch of primaries first hop flag when forwarding */
 597         batadv_ogm_packet->flags &= ~BATADV_PRIMARIES_FIRST_HOP;
 598         if (is_single_hop_neigh)
 599                 batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 600         else
 601                 batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 602
 603         batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
 604                                 BATADV_OGM_HLEN + batadv_tt_len(tt_num_changes),
 605                                 if_incoming, 0, batadv_iv_ogm_fwd_send_time());
 606 }
 607
 608 static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
 609 {
 610         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 611         unsigned char **ogm_buff = &hard_iface->bat_iv.ogm_buff;
 612         struct batadv_ogm_packet *batadv_ogm_packet;
 613         struct batadv_hard_iface *primary_if;
 614         int *ogm_buff_len = &hard_iface->bat_iv.ogm_buff_len;
 615         int vis_server, tt_num_changes = 0;
 616         uint32_t seqno;
 617         uint8_t bandwidth;
 618
 619         vis_server = atomic_read(&bat_priv->vis_mode);
 620         primary_if = batadv_primary_if_get_selected(bat_priv);
 621
 622         if (hard_iface == primary_if)
 623                 tt_num_changes = batadv_tt_append_diff(bat_priv, ogm_buff,
 624                                                        ogm_buff_len,
 625                                                        BATADV_OGM_HLEN);
 626
 627         batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff);
 628
 629         /* change sequence number to network order */
 630         seqno = (uint32_t)atomic_read(&hard_iface->bat_iv.ogm_seqno);
 631         batadv_ogm_packet->seqno = htonl(seqno);
 632         atomic_inc(&hard_iface->bat_iv.ogm_seqno);
 633
 634         batadv_ogm_packet->ttvn = atomic_read(&bat_priv->tt.vn);
 635         batadv_ogm_packet->tt_crc = htons(bat_priv->tt.local_crc);
 636         if (tt_num_changes >= 0)
 637                 batadv_ogm_packet->tt_num_changes = tt_num_changes;
 638
 639         if (vis_server == BATADV_VIS_TYPE_SERVER_SYNC)
 640                 batadv_ogm_packet->flags |= BATADV_VIS_SERVER;
 641         else
 642                 batadv_ogm_packet->flags &= ~BATADV_VIS_SERVER;
 643
 644         if (hard_iface == primary_if &&
 645             atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_SERVER) {
 646                 bandwidth = (uint8_t)atomic_read(&bat_priv->gw_bandwidth);
 647                 batadv_ogm_packet->gw_flags = bandwidth;
 648         } else {
 649                 batadv_ogm_packet->gw_flags = BATADV_NO_FLAGS;
 650         }
 651
 652         batadv_slide_own_bcast_window(hard_iface);
 653         batadv_iv_ogm_queue_add(bat_priv, hard_iface->bat_iv.ogm_buff,
 654                                 hard_iface->bat_iv.ogm_buff_len, hard_iface, 1,
 655                                 batadv_iv_ogm_emit_send_time(bat_priv));
 656
 657         if (primary_if)
 658                 batadv_hardif_free_ref(primary_if);
 659 }
 660
 661 static void
 662 batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv,
 663                           struct batadv_orig_node *orig_node,
 664                           const struct ethhdr *ethhdr,
 665                           const struct batadv_ogm_packet *batadv_ogm_packet,
 666                           struct batadv_hard_iface *if_incoming,
 667                           const unsigned char *tt_buff,
 668                           enum batadv_dup_status dup_status)
 669 {
 670         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 671         struct batadv_neigh_node *router = NULL;
 672         struct batadv_orig_node *orig_node_tmp;
 673         int if_num;
 674         uint8_t sum_orig, sum_neigh;
 675         uint8_t *neigh_addr;
 676         uint8_t tq_avg;
 677
 678         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 679                    "update_originator(): Searching and updating originator entry of received packet\n");
 680
 681         rcu_read_lock();
 682         hlist_for_each_entry_rcu(tmp_neigh_node,
 683                                  &orig_node->neigh_list, list) {
 684                 neigh_addr = tmp_neigh_node->addr;
 685                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 686                     tmp_neigh_node->if_incoming == if_incoming &&
 687                     atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
 688                         if (neigh_node)
 689                                 batadv_neigh_node_free_ref(neigh_node);
 690                         neigh_node = tmp_neigh_node;
 691                         continue;
 692                 }
 693
 694                 if (dup_status != BATADV_NO_DUP)
 695                         continue;
 696
 697                 spin_lock_bh(&tmp_neigh_node->lq_update_lock);
 698                 batadv_ring_buffer_set(tmp_neigh_node->tq_recv,
 699                                        &tmp_neigh_node->tq_index, 0);
 700                 tq_avg = batadv_ring_buffer_avg(tmp_neigh_node->tq_recv);
 701                 tmp_neigh_node->tq_avg = tq_avg;
 702                 spin_unlock_bh(&tmp_neigh_node->lq_update_lock);
 703         }
 704
 705         if (!neigh_node) {
 706                 struct batadv_orig_node *orig_tmp;
 707
 708                 orig_tmp = batadv_get_orig_node(bat_priv, ethhdr->h_source);
 709                 if (!orig_tmp)
 710                         goto unlock;
 711
 712                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 713                                                      ethhdr->h_source,
 714                                                      orig_node, orig_tmp,
 715                                                      batadv_ogm_packet->seqno);
 716
 717                 batadv_orig_node_free_ref(orig_tmp);
 718                 if (!neigh_node)
 719                         goto unlock;
 720         } else
 721                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 722                            "Updating existing last-hop neighbor of originator\n");
 723
 724         rcu_read_unlock();
 725
 726         orig_node->flags = batadv_ogm_packet->flags;
 727         neigh_node->last_seen = jiffies;
 728
 729         spin_lock_bh(&neigh_node->lq_update_lock);
 730         batadv_ring_buffer_set(neigh_node->tq_recv,
 731                                &neigh_node->tq_index,
 732                                batadv_ogm_packet->tq);
 733         neigh_node->tq_avg = batadv_ring_buffer_avg(neigh_node->tq_recv);
 734         spin_unlock_bh(&neigh_node->lq_update_lock);
 735
 736         if (dup_status == BATADV_NO_DUP) {
 737                 orig_node->last_ttl = batadv_ogm_packet->header.ttl;
 738                 neigh_node->last_ttl = batadv_ogm_packet->header.ttl;
 739         }
 740
 741         batadv_bonding_candidate_add(orig_node, neigh_node);
 742
 743         /* if this neighbor already is our next hop there is nothing
 744          * to change
 745          */
 746         router = batadv_orig_node_get_router(orig_node);
 747         if (router == neigh_node)
 748                 goto update_tt;
 749
 750         /* if this neighbor does not offer a better TQ we won't consider it */
 751         if (router && (router->tq_avg > neigh_node->tq_avg))
 752                 goto update_tt;
 753
 754         /* if the TQ is the same and the link not more symmetric we
 755          * won't consider it either
 756          */
 757         if (router && (neigh_node->tq_avg == router->tq_avg)) {
 758                 orig_node_tmp = router->orig_node;
 759                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 760                 if_num = router->if_incoming->if_num;
 761                 sum_orig = orig_node_tmp->bcast_own_sum[if_num];
 762                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 763
 764                 orig_node_tmp = neigh_node->orig_node;
 765                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 766                 if_num = neigh_node->if_incoming->if_num;
 767                 sum_neigh = orig_node_tmp->bcast_own_sum[if_num];
 768                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 769
 770                 if (sum_orig >= sum_neigh)
 771                         goto update_tt;
 772         }
 773
 774         batadv_update_route(bat_priv, orig_node, neigh_node);
 775
 776 update_tt:
 777         /* I have to check for transtable changes only if the OGM has been
 778          * sent through a primary interface
 779          */
 780         if (((batadv_ogm_packet->orig != ethhdr->h_source) &&
 781              (batadv_ogm_packet->header.ttl > 2)) ||
 782             (batadv_ogm_packet->flags & BATADV_PRIMARIES_FIRST_HOP))
 783                 batadv_tt_update_orig(bat_priv, orig_node, tt_buff,
 784                                       batadv_ogm_packet->tt_num_changes,
 785                                       batadv_ogm_packet->ttvn,
 786                                       ntohs(batadv_ogm_packet->tt_crc));
 787
 788         if (orig_node->gw_flags != batadv_ogm_packet->gw_flags)
 789                 batadv_gw_node_update(bat_priv, orig_node,
 790                                       batadv_ogm_packet->gw_flags);
 791
 792         orig_node->gw_flags = batadv_ogm_packet->gw_flags;
 793
 794         /* restart gateway selection if fast or late switching was enabled */
 795         if ((orig_node->gw_flags) &&
 796             (atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_CLIENT) &&
 797             (atomic_read(&bat_priv->gw_sel_class) > 2))
 798                 batadv_gw_check_election(bat_priv, orig_node);
 799
 800         goto out;
 801
 802 unlock:
 803         rcu_read_unlock();
 804 out:
 805         if (neigh_node)
 806                 batadv_neigh_node_free_ref(neigh_node);
 807         if (router)
 808                 batadv_neigh_node_free_ref(router);
 809 }
 810
 811 static int batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
 812                                  struct batadv_orig_node *orig_neigh_node,
 813                                  struct batadv_ogm_packet *batadv_ogm_packet,
 814                                  struct batadv_hard_iface *if_incoming)
 815 {
 816         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 817         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node;
 818         uint8_t total_count;
 819         uint8_t orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
 820         unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
 821         int tq_asym_penalty, inv_asym_penalty, ret = 0;
 822         unsigned int combined_tq;
 823
 824         /* find corresponding one hop neighbor */
 825         rcu_read_lock();
 826         hlist_for_each_entry_rcu(tmp_neigh_node,
 827                                  &orig_neigh_node->neigh_list, list) {
 828                 if (!batadv_compare_eth(tmp_neigh_node->addr,
 829                                         orig_neigh_node->orig))
 830                         continue;
 831
 832                 if (tmp_neigh_node->if_incoming != if_incoming)
 833                         continue;
 834
 835                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 836                         continue;
 837
 838                 neigh_node = tmp_neigh_node;
 839                 break;
 840         }
 841         rcu_read_unlock();
 842
 843         if (!neigh_node)
 844                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 845                                                      orig_neigh_node->orig,
 846                                                      orig_neigh_node,
 847                                                      orig_neigh_node,
 848                                                      batadv_ogm_packet->seqno);
 849
 850         if (!neigh_node)
 851                 goto out;
 852
 853         /* if orig_node is direct neighbor update neigh_node last_seen */
 854         if (orig_node == orig_neigh_node)
 855                 neigh_node->last_seen = jiffies;
 856
 857         orig_node->last_seen = jiffies;
 858
 859         /* find packet count of corresponding one hop neighbor */
 860         spin_lock_bh(&orig_node->ogm_cnt_lock);
 861         orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
 862         neigh_rq_count = neigh_node->real_packet_count;
 863         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 864
 865         /* pay attention to not get a value bigger than 100 % */
 866         if (orig_eq_count > neigh_rq_count)
 867                 total_count = neigh_rq_count;
 868         else
 869                 total_count = orig_eq_count;
 870
 871         /* if we have too few packets (too less data) we set tq_own to zero
 872          * if we receive too few packets it is not considered bidirectional
 873          */
 874         if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
 875             neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
 876                 tq_own = 0;
 877         else
 878                 /* neigh_node->real_packet_count is never zero as we
 879                  * only purge old information when getting new
 880                  * information
 881                  */
 882                 tq_own = (BATADV_TQ_MAX_VALUE * total_count) /  neigh_rq_count;
 883
 884         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 885          * affect the nearly-symmetric links only a little, but
 886          * punishes asymmetric links more.  This will give a value
 887          * between 0 and TQ_MAX_VALUE
 888          */
 889         neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
 890         neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
 891         neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
 892                             BATADV_TQ_LOCAL_WINDOW_SIZE *
 893                             BATADV_TQ_LOCAL_WINDOW_SIZE;
 894         inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
 895         inv_asym_penalty /= neigh_rq_max_cube;
 896         tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;
 897
 898         combined_tq = batadv_ogm_packet->tq * tq_own * tq_asym_penalty;
 899         combined_tq /= BATADV_TQ_MAX_VALUE * BATADV_TQ_MAX_VALUE;
 900         batadv_ogm_packet->tq = combined_tq;
 901
 902         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 903                    "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n",
 904                    orig_node->orig, orig_neigh_node->orig, total_count,
 905                    neigh_rq_count, tq_own,
 906                    tq_asym_penalty, batadv_ogm_packet->tq);
 907
 908         /* if link has the minimum required transmission quality
 909          * consider it bidirectional
 910          */
 911         if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
 912                 ret = 1;
 913
 914 out:
 915         if (neigh_node)
 916                 batadv_neigh_node_free_ref(neigh_node);
 917         return ret;
 918 }
 919
 920 /**
 921  * batadv_iv_ogm_update_seqnos -  process a batman packet for all interfaces,
 922  *  adjust the sequence number and find out whether it is a duplicate
 923  * @ethhdr: ethernet header of the packet
 924  * @batadv_ogm_packet: OGM packet to be considered
 925  * @if_incoming: interface on which the OGM packet was received
 926  *
 927  * Returns duplicate status as enum batadv_dup_status
 928  */
 929 static enum batadv_dup_status
 930 batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
 931                             const struct batadv_ogm_packet *batadv_ogm_packet,
 932                             const struct batadv_hard_iface *if_incoming)
 933 {
 934         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 935         struct batadv_orig_node *orig_node;
 936         struct batadv_neigh_node *tmp_neigh_node;
 937         int is_dup;
 938         int32_t seq_diff;
 939         int need_update = 0;
 940         int set_mark;
 941         enum batadv_dup_status ret = BATADV_NO_DUP;
 942         uint32_t seqno = ntohl(batadv_ogm_packet->seqno);
 943         uint8_t *neigh_addr;
 944         uint8_t packet_count;
 945
 946         orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig);
 947         if (!orig_node)
 948                 return BATADV_NO_DUP;
 949
 950         spin_lock_bh(&orig_node->ogm_cnt_lock);
 951         seq_diff = seqno - orig_node->last_real_seqno;
 952
 953         /* signalize caller that the packet is to be dropped. */
 954         if (!hlist_empty(&orig_node->neigh_list) &&
 955             batadv_window_protected(bat_priv, seq_diff,
 956                                     &orig_node->batman_seqno_reset)) {
 957                 ret = BATADV_PROTECTED;
 958                 goto out;
 959         }
 960
 961         rcu_read_lock();
 962         hlist_for_each_entry_rcu(tmp_neigh_node,
 963                                  &orig_node->neigh_list, list) {
 964                 neigh_addr = tmp_neigh_node->addr;
 965                 is_dup = batadv_test_bit(tmp_neigh_node->real_bits,
 966                                          orig_node->last_real_seqno,
 967                                          seqno);
 968
 969                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 970                     tmp_neigh_node->if_incoming == if_incoming) {
 971                         set_mark = 1;
 972                         if (is_dup)
 973                                 ret = BATADV_NEIGH_DUP;
 974                 } else {
 975                         set_mark = 0;
 976                         if (is_dup && (ret != BATADV_NEIGH_DUP))
 977                                 ret = BATADV_ORIG_DUP;
 978                 }
 979
 980                 /* if the window moved, set the update flag. */
 981                 need_update |= batadv_bit_get_packet(bat_priv,
 982                                                      tmp_neigh_node->real_bits,
 983                                                      seq_diff, set_mark);
 984
 985                 packet_count = bitmap_weight(tmp_neigh_node->real_bits,
 986                                              BATADV_TQ_LOCAL_WINDOW_SIZE);
 987                 tmp_neigh_node->real_packet_count = packet_count;
 988         }
 989         rcu_read_unlock();
 990
 991         if (need_update) {
 992                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 993                            "updating last_seqno: old %u, new %u\n",
 994                            orig_node->last_real_seqno, seqno);
 995                 orig_node->last_real_seqno = seqno;
 996         }
 997
 998 out:
 999         spin_unlock_bh(&orig_node->ogm_cnt_lock);
1000         batadv_orig_node_free_ref(orig_node);
1001         return ret;
1002 }
1003
1004 static void batadv_iv_ogm_process(const struct ethhdr *ethhdr,
1005                                   struct batadv_ogm_packet *batadv_ogm_packet,
1006                                   const unsigned char *tt_buff,
1007                                   struct batadv_hard_iface *if_incoming)
1008 {
1009         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1010         struct batadv_hard_iface *hard_iface;
1011         struct batadv_orig_node *orig_neigh_node, *orig_node;
1012         struct batadv_neigh_node *router = NULL, *router_router = NULL;
1013         struct batadv_neigh_node *orig_neigh_router = NULL;
1014         int has_directlink_flag;
1015         int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
1016         int is_broadcast = 0, is_bidirect;
1017         bool is_single_hop_neigh = false;
1018         bool is_from_best_next_hop = false;
1019         int sameseq, similar_ttl;
1020         enum batadv_dup_status dup_status;
1021         uint32_t if_incoming_seqno;
1022         uint8_t *prev_sender;
1023
1024         /* Silently drop when the batman packet is actually not a
1025          * correct packet.
1026          *
1027          * This might happen if a packet is padded (e.g. Ethernet has a
1028          * minimum frame length of 64 byte) and the aggregation interprets
1029          * it as an additional length.
1030          *
1031          * TODO: A more sane solution would be to have a bit in the
1032          * batadv_ogm_packet to detect whether the packet is the last
1033          * packet in an aggregation.  Here we expect that the padding
1034          * is always zero (or not 0x01)
1035          */
1036         if (batadv_ogm_packet->header.packet_type != BATADV_IV_OGM)
1037                 return;
1038
1039         /* could be changed by schedule_own_packet() */
1040         if_incoming_seqno = atomic_read(&if_incoming->bat_iv.ogm_seqno);
1041
1042         if (batadv_ogm_packet->flags & BATADV_DIRECTLINK)
1043                 has_directlink_flag = 1;
1044         else
1045                 has_directlink_flag = 0;
1046
1047         if (batadv_compare_eth(ethhdr->h_source, batadv_ogm_packet->orig))
1048                 is_single_hop_neigh = true;
1049
1050         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1051                    "Received BATMAN packet via NB: %pM, IF: %s [%pM] (from OG: %pM, via prev OG: %pM, seqno %u, ttvn %u, crc %#.4x, changes %u, tq %d, TTL %d, V %d, IDF %d)\n",
1052                    ethhdr->h_source, if_incoming->net_dev->name,
1053                    if_incoming->net_dev->dev_addr, batadv_ogm_packet->orig,
1054                    batadv_ogm_packet->prev_sender,
1055                    ntohl(batadv_ogm_packet->seqno), batadv_ogm_packet->ttvn,
1056                    ntohs(batadv_ogm_packet->tt_crc),
1057                    batadv_ogm_packet->tt_num_changes, batadv_ogm_packet->tq,
1058                    batadv_ogm_packet->header.ttl,
1059                    batadv_ogm_packet->header.version, has_directlink_flag);
1060
1061         rcu_read_lock();
1062         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1063                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
1064                         continue;
1065
1066                 if (hard_iface->soft_iface != if_incoming->soft_iface)
1067                         continue;
1068
1069                 if (batadv_compare_eth(ethhdr->h_source,
1070                                        hard_iface->net_dev->dev_addr))
1071                         is_my_addr = 1;
1072
1073                 if (batadv_compare_eth(batadv_ogm_packet->orig,
1074                                        hard_iface->net_dev->dev_addr))
1075                         is_my_orig = 1;
1076
1077                 if (batadv_compare_eth(batadv_ogm_packet->prev_sender,
1078                                        hard_iface->net_dev->dev_addr))
1079                         is_my_oldorig = 1;
1080
1081                 if (is_broadcast_ether_addr(ethhdr->h_source))
1082                         is_broadcast = 1;
1083         }
1084         rcu_read_unlock();
1085
1086         if (batadv_ogm_packet->header.version != BATADV_COMPAT_VERSION) {
1087                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1088                            "Drop packet: incompatible batman version (%i)\n",
1089                            batadv_ogm_packet->header.version);
1090                 return;
1091         }
1092
1093         if (is_my_addr) {
1094                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1095                            "Drop packet: received my own broadcast (sender: %pM)\n",
1096                            ethhdr->h_source);
1097                 return;
1098         }
1099
1100         if (is_broadcast) {
1101                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1102                            "Drop packet: ignoring all packets with broadcast source addr (sender: %pM)\n",
1103                            ethhdr->h_source);
1104                 return;
1105         }
1106
1107         if (is_my_orig) {
1108                 unsigned long *word;
1109                 int offset;
1110                 int32_t bit_pos;
1111                 int16_t if_num;
1112                 uint8_t *weight;
1113
1114                 orig_neigh_node = batadv_get_orig_node(bat_priv,
1115                                                        ethhdr->h_source);
1116                 if (!orig_neigh_node)
1117                         return;
1118
1119                 /* neighbor has to indicate direct link and it has to
1120                  * come via the corresponding interface
1121                  * save packet seqno for bidirectional check
1122                  */
1123                 if (has_directlink_flag &&
1124                     batadv_compare_eth(if_incoming->net_dev->dev_addr,
1125                                        batadv_ogm_packet->orig)) {
1126                         if_num = if_incoming->if_num;
1127                         offset = if_num * BATADV_NUM_WORDS;
1128
1129                         spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
1130                         word = &(orig_neigh_node->bcast_own[offset]);
1131                         bit_pos = if_incoming_seqno - 2;
1132                         bit_pos -= ntohl(batadv_ogm_packet->seqno);
1133                         batadv_set_bit(word, bit_pos);
1134                         weight = &orig_neigh_node->bcast_own_sum[if_num];
1135                         *weight = bitmap_weight(word,
1136                                                 BATADV_TQ_LOCAL_WINDOW_SIZE);
1137                         spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
1138                 }
1139
1140                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1141                            "Drop packet: originator packet from myself (via neighbor)\n");
1142                 batadv_orig_node_free_ref(orig_neigh_node);
1143                 return;
1144         }
1145
1146         if (is_my_oldorig) {
1147                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1148                            "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1149                            ethhdr->h_source);
1150                 return;
1151         }
1152
1153         if (batadv_ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) {
1154                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1155                            "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1156                            ethhdr->h_source);
1157                 return;
1158         }
1159
1160         orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig);
1161         if (!orig_node)
1162                 return;
1163
1164         dup_status = batadv_iv_ogm_update_seqnos(ethhdr, batadv_ogm_packet,
1165                                                  if_incoming);
1166
1167         if (dup_status == BATADV_PROTECTED) {
1168                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1169                            "Drop packet: packet within seqno protection time (sender: %pM)\n",
1170                            ethhdr->h_source);
1171                 goto out;
1172         }
1173
1174         if (batadv_ogm_packet->tq == 0) {
1175                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1176                            "Drop packet: originator packet with tq equal 0\n");
1177                 goto out;
1178         }
1179
1180         router = batadv_orig_node_get_router(orig_node);
1181         if (router)
1182                 router_router = batadv_orig_node_get_router(router->orig_node);
1183
1184         if ((router && router->tq_avg != 0) &&
1185             (batadv_compare_eth(router->addr, ethhdr->h_source)))
1186                 is_from_best_next_hop = true;
1187
1188         prev_sender = batadv_ogm_packet->prev_sender;
1189         /* avoid temporary routing loops */
1190         if (router && router_router &&
1191             (batadv_compare_eth(router->addr, prev_sender)) &&
1192             !(batadv_compare_eth(batadv_ogm_packet->orig, prev_sender)) &&
1193             (batadv_compare_eth(router->addr, router_router->addr))) {
1194                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1195                            "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1196                            ethhdr->h_source);
1197                 goto out;
1198         }
1199
1200         /* if sender is a direct neighbor the sender mac equals
1201          * originator mac
1202          */
1203         if (is_single_hop_neigh)
1204                 orig_neigh_node = orig_node;
1205         else
1206                 orig_neigh_node = batadv_get_orig_node(bat_priv,
1207                                                        ethhdr->h_source);
1208
1209         if (!orig_neigh_node)
1210                 goto out;
1211
1212         /* Update nc_nodes of the originator */
1213         batadv_nc_update_nc_node(bat_priv, orig_node, orig_neigh_node,
1214                                  batadv_ogm_packet, is_single_hop_neigh);
1215
1216         orig_neigh_router = batadv_orig_node_get_router(orig_neigh_node);
1217
1218         /* drop packet if sender is not a direct neighbor and if we
1219          * don't route towards it
1220          */
1221         if (!is_single_hop_neigh && (!orig_neigh_router)) {
1222                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1223                            "Drop packet: OGM via unknown neighbor!\n");
1224                 goto out_neigh;
1225         }
1226
1227         is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1228                                             batadv_ogm_packet, if_incoming);
1229
1230         batadv_bonding_save_primary(orig_node, orig_neigh_node,
1231                                     batadv_ogm_packet);
1232
1233         /* update ranking if it is not a duplicate or has the same
1234          * seqno and similar ttl as the non-duplicate
1235          */
1236         sameseq = orig_node->last_real_seqno == ntohl(batadv_ogm_packet->seqno);
1237         similar_ttl = orig_node->last_ttl - 3 <= batadv_ogm_packet->header.ttl;
1238         if (is_bidirect && ((dup_status == BATADV_NO_DUP) ||
1239                             (sameseq && similar_ttl)))
1240                 batadv_iv_ogm_orig_update(bat_priv, orig_node, ethhdr,
1241                                           batadv_ogm_packet, if_incoming,
1242                                           tt_buff, dup_status);
1243
1244         /* is single hop (direct) neighbor */
1245         if (is_single_hop_neigh) {
1246                 /* mark direct link on incoming interface */
1247                 batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1248                                       is_single_hop_neigh,
1249                                       is_from_best_next_hop, if_incoming);
1250
1251                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1252                            "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1253                 goto out_neigh;
1254         }
1255
1256         /* multihop originator */
1257         if (!is_bidirect) {
1258                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1259                            "Drop packet: not received via bidirectional link\n");
1260                 goto out_neigh;
1261         }
1262
1263         if (dup_status == BATADV_NEIGH_DUP) {
1264                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1265                            "Drop packet: duplicate packet received\n");
1266                 goto out_neigh;
1267         }
1268
1269         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1270                    "Forwarding packet: rebroadcast originator packet\n");
1271         batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1272                               is_single_hop_neigh, is_from_best_next_hop,
1273                               if_incoming);
1274
1275 out_neigh:
1276         if ((orig_neigh_node) && (!is_single_hop_neigh))
1277                 batadv_orig_node_free_ref(orig_neigh_node);
1278 out:
1279         if (router)
1280                 batadv_neigh_node_free_ref(router);
1281         if (router_router)
1282                 batadv_neigh_node_free_ref(router_router);
1283         if (orig_neigh_router)
1284                 batadv_neigh_node_free_ref(orig_neigh_router);
1285
1286         batadv_orig_node_free_ref(orig_node);
1287 }
1288
1289 static int batadv_iv_ogm_receive(struct sk_buff *skb,
1290                                  struct batadv_hard_iface *if_incoming)
1291 {
1292         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1293         struct batadv_ogm_packet *batadv_ogm_packet;
1294         struct ethhdr *ethhdr;
1295         int buff_pos = 0, packet_len;
1296         unsigned char *tt_buff, *packet_buff;
1297         bool ret;
1298         uint8_t *packet_pos;
1299
1300         ret = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
1301         if (!ret)
1302                 return NET_RX_DROP;
1303
1304         /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1305          * that does not have B.A.T.M.A.N. IV enabled ?
1306          */
1307         if (bat_priv->bat_algo_ops->bat_ogm_emit != batadv_iv_ogm_emit)
1308                 return NET_RX_DROP;
1309
1310         batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
1311         batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
1312                            skb->len + ETH_HLEN);
1313
1314         packet_len = skb_headlen(skb);
1315         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1316         packet_buff = skb->data;
1317         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
1318
1319         /* unpack the aggregated packets and process them one by one */
1320         while (batadv_iv_ogm_aggr_packet(buff_pos, packet_len,
1321                                          batadv_ogm_packet->tt_num_changes)) {
1322                 tt_buff = packet_buff + buff_pos + BATADV_OGM_HLEN;
1323
1324                 batadv_iv_ogm_process(ethhdr, batadv_ogm_packet, tt_buff,
1325                                       if_incoming);
1326
1327                 buff_pos += BATADV_OGM_HLEN;
1328                 buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
1329
1330                 packet_pos = packet_buff + buff_pos;
1331                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
1332         }
1333
1334         kfree_skb(skb);
1335         return NET_RX_SUCCESS;
1336 }
1337
1338 static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
1339         .name = "BATMAN_IV",
1340         .bat_iface_enable = batadv_iv_ogm_iface_enable,
1341         .bat_iface_disable = batadv_iv_ogm_iface_disable,
1342         .bat_iface_update_mac = batadv_iv_ogm_iface_update_mac,
1343         .bat_primary_iface_set = batadv_iv_ogm_primary_iface_set,
1344         .bat_ogm_schedule = batadv_iv_ogm_schedule,
1345         .bat_ogm_emit = batadv_iv_ogm_emit,
1346 };
1347
1348 int __init batadv_iv_init(void)
1349 {
1350         int ret;
1351
1352         /* batman originator packet */
1353         ret = batadv_recv_handler_register(BATADV_IV_OGM,
1354                                            batadv_iv_ogm_receive);
1355         if (ret < 0)
1356                 goto out;
1357
1358         ret = batadv_algo_register(&batadv_batman_iv);
1359         if (ret < 0)
1360                 goto handler_unregister;
1361
1362         goto out;
1363
1364 handler_unregister:
1365         batadv_recv_handler_unregister(BATADV_IV_OGM);
1366 out:
1367         return ret;
1368 }