net/batman-adv/bat_iv_ogm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (C) B.A.T.M.A.N. contributors:
   3  *
   4  * Marek Lindner, Simon Wunderlich
   5  */
   6
   7 #include "bat_iv_ogm.h"
   8 #include "main.h"
   9
  10 #include <linux/atomic.h>
  11 #include <linux/bitmap.h>
  12 #include <linux/bitops.h>
  13 #include <linux/bug.h>
  14 #include <linux/byteorder/generic.h>
  15 #include <linux/cache.h>
  16 #include <linux/errno.h>
  17 #include <linux/etherdevice.h>
  18 #include <linux/gfp.h>
  19 #include <linux/if_ether.h>
  20 #include <linux/init.h>
  21 #include <linux/jiffies.h>
  22 #include <linux/kernel.h>
  23 #include <linux/kref.h>
  24 #include <linux/list.h>
  25 #include <linux/lockdep.h>
  26 #include <linux/mutex.h>
  27 #include <linux/netdevice.h>
  28 #include <linux/netlink.h>
  29 #include <linux/pkt_sched.h>
  30 #include <linux/prandom.h>
  31 #include <linux/printk.h>
  32 #include <linux/random.h>
  33 #include <linux/rculist.h>
  34 #include <linux/rcupdate.h>
  35 #include <linux/skbuff.h>
  36 #include <linux/slab.h>
  37 #include <linux/spinlock.h>
  38 #include <linux/stddef.h>
  39 #include <linux/string.h>
  40 #include <linux/types.h>
  41 #include <linux/workqueue.h>
  42 #include <net/genetlink.h>
  43 #include <net/netlink.h>
  44 #include <uapi/linux/batadv_packet.h>
  45 #include <uapi/linux/batman_adv.h>
  46
  47 #include "bat_algo.h"
  48 #include "bitarray.h"
  49 #include "gateway_client.h"
  50 #include "hard-interface.h"
  51 #include "hash.h"
  52 #include "log.h"
  53 #include "netlink.h"
  54 #include "network-coding.h"
  55 #include "originator.h"
  56 #include "routing.h"
  57 #include "send.h"
  58 #include "translation-table.h"
  59 #include "tvlv.h"
  60
  61 static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work);
  62
  63 /**
  64  * enum batadv_dup_status - duplicate status
  65  */
  66 enum batadv_dup_status {
  67         /** @BATADV_NO_DUP: the packet is no duplicate */
  68         BATADV_NO_DUP = 0,
  69
  70         /**
  71          * @BATADV_ORIG_DUP: OGM is a duplicate in the originator (but not for
  72          *  the neighbor)
  73          */
  74         BATADV_ORIG_DUP,
  75
  76         /** @BATADV_NEIGH_DUP: OGM is a duplicate for the neighbor */
  77         BATADV_NEIGH_DUP,
  78
  79         /**
  80          * @BATADV_PROTECTED: originator is currently protected (after reboot)
  81          */
  82         BATADV_PROTECTED,
  83 };
  84
  85 /**
  86  * batadv_ring_buffer_set() - update the ring buffer with the given value
  87  * @lq_recv: pointer to the ring buffer
  88  * @lq_index: index to store the value at
  89  * @value: value to store in the ring buffer
  90  */
  91 static void batadv_ring_buffer_set(u8 lq_recv[], u8 *lq_index, u8 value)
  92 {
  93         lq_recv[*lq_index] = value;
  94         *lq_index = (*lq_index + 1) % BATADV_TQ_GLOBAL_WINDOW_SIZE;
  95 }
  96
  97 /**
  98  * batadv_ring_buffer_avg() - compute the average of all non-zero values stored
  99  * in the given ring buffer
 100  * @lq_recv: pointer to the ring buffer
 101  *
 102  * Return: computed average value.
 103  */
 104 static u8 batadv_ring_buffer_avg(const u8 lq_recv[])
 105 {
 106         const u8 *ptr;
 107         u16 count = 0;
 108         u16 i = 0;
 109         u16 sum = 0;
 110
 111         ptr = lq_recv;
 112
 113         while (i < BATADV_TQ_GLOBAL_WINDOW_SIZE) {
 114                 if (*ptr != 0) {
 115                         count++;
 116                         sum += *ptr;
 117                 }
 118
 119                 i++;
 120                 ptr++;
 121         }
 122
 123         if (count == 0)
 124                 return 0;
 125
 126         return (u8)(sum / count);
 127 }
 128
 129 /**
 130  * batadv_iv_ogm_orig_get() - retrieve or create (if does not exist) an
 131  *  originator
 132  * @bat_priv: the bat priv with all the soft interface information
 133  * @addr: mac address of the originator
 134  *
 135  * Return: the originator object corresponding to the passed mac address or NULL
 136  * on failure.
 137  * If the object does not exist, it is created and initialised.
 138  */
 139 static struct batadv_orig_node *
 140 batadv_iv_ogm_orig_get(struct batadv_priv *bat_priv, const u8 *addr)
 141 {
 142         struct batadv_orig_node *orig_node;
 143         int hash_added;
 144
 145         orig_node = batadv_orig_hash_find(bat_priv, addr);
 146         if (orig_node)
 147                 return orig_node;
 148
 149         orig_node = batadv_orig_node_new(bat_priv, addr);
 150         if (!orig_node)
 151                 return NULL;
 152
 153         spin_lock_init(&orig_node->bat_iv.ogm_cnt_lock);
 154
 155         kref_get(&orig_node->refcount);
 156         hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig,
 157                                      batadv_choose_orig, orig_node,
 158                                      &orig_node->hash_entry);
 159         if (hash_added != 0)
 160                 goto free_orig_node_hash;
 161
 162         return orig_node;
 163
 164 free_orig_node_hash:
 165         /* reference for batadv_hash_add */
 166         batadv_orig_node_put(orig_node);
 167         /* reference from batadv_orig_node_new */
 168         batadv_orig_node_put(orig_node);
 169
 170         return NULL;
 171 }
 172
 173 static struct batadv_neigh_node *
 174 batadv_iv_ogm_neigh_new(struct batadv_hard_iface *hard_iface,
 175                         const u8 *neigh_addr,
 176                         struct batadv_orig_node *orig_node,
 177                         struct batadv_orig_node *orig_neigh)
 178 {
 179         struct batadv_neigh_node *neigh_node;
 180
 181         neigh_node = batadv_neigh_node_get_or_create(orig_node,
 182                                                      hard_iface, neigh_addr);
 183         if (!neigh_node)
 184                 goto out;
 185
 186         neigh_node->orig_node = orig_neigh;
 187
 188 out:
 189         return neigh_node;
 190 }
 191
 192 static int batadv_iv_ogm_iface_enable(struct batadv_hard_iface *hard_iface)
 193 {
 194         struct batadv_ogm_packet *batadv_ogm_packet;
 195         unsigned char *ogm_buff;
 196         u32 random_seqno;
 197
 198         mutex_lock(&hard_iface->bat_iv.ogm_buff_mutex);
 199
 200         /* randomize initial seqno to avoid collision */
 201         get_random_bytes(&random_seqno, sizeof(random_seqno));
 202         atomic_set(&hard_iface->bat_iv.ogm_seqno, random_seqno);
 203
 204         hard_iface->bat_iv.ogm_buff_len = BATADV_OGM_HLEN;
 205         ogm_buff = kmalloc(hard_iface->bat_iv.ogm_buff_len, GFP_ATOMIC);
 206         if (!ogm_buff) {
 207                 mutex_unlock(&hard_iface->bat_iv.ogm_buff_mutex);
 208                 return -ENOMEM;
 209         }
 210
 211         hard_iface->bat_iv.ogm_buff = ogm_buff;
 212
 213         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 214         batadv_ogm_packet->packet_type = BATADV_IV_OGM;
 215         batadv_ogm_packet->version = BATADV_COMPAT_VERSION;
 216         batadv_ogm_packet->ttl = 2;
 217         batadv_ogm_packet->flags = BATADV_NO_FLAGS;
 218         batadv_ogm_packet->reserved = 0;
 219         batadv_ogm_packet->tq = BATADV_TQ_MAX_VALUE;
 220
 221         mutex_unlock(&hard_iface->bat_iv.ogm_buff_mutex);
 222
 223         return 0;
 224 }
 225
 226 static void batadv_iv_ogm_iface_disable(struct batadv_hard_iface *hard_iface)
 227 {
 228         mutex_lock(&hard_iface->bat_iv.ogm_buff_mutex);
 229
 230         kfree(hard_iface->bat_iv.ogm_buff);
 231         hard_iface->bat_iv.ogm_buff = NULL;
 232
 233         mutex_unlock(&hard_iface->bat_iv.ogm_buff_mutex);
 234 }
 235
 236 static void batadv_iv_ogm_iface_update_mac(struct batadv_hard_iface *hard_iface)
 237 {
 238         struct batadv_ogm_packet *batadv_ogm_packet;
 239         void *ogm_buff;
 240
 241         mutex_lock(&hard_iface->bat_iv.ogm_buff_mutex);
 242
 243         ogm_buff = hard_iface->bat_iv.ogm_buff;
 244         if (!ogm_buff)
 245                 goto unlock;
 246
 247         batadv_ogm_packet = ogm_buff;
 248         ether_addr_copy(batadv_ogm_packet->orig,
 249                         hard_iface->net_dev->dev_addr);
 250         ether_addr_copy(batadv_ogm_packet->prev_sender,
 251                         hard_iface->net_dev->dev_addr);
 252
 253 unlock:
 254         mutex_unlock(&hard_iface->bat_iv.ogm_buff_mutex);
 255 }
 256
 257 static void
 258 batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface)
 259 {
 260         struct batadv_ogm_packet *batadv_ogm_packet;
 261         void *ogm_buff;
 262
 263         mutex_lock(&hard_iface->bat_iv.ogm_buff_mutex);
 264
 265         ogm_buff = hard_iface->bat_iv.ogm_buff;
 266         if (!ogm_buff)
 267                 goto unlock;
 268
 269         batadv_ogm_packet = ogm_buff;
 270         batadv_ogm_packet->ttl = BATADV_TTL;
 271
 272 unlock:
 273         mutex_unlock(&hard_iface->bat_iv.ogm_buff_mutex);
 274 }
 275
 276 /* when do we schedule our own ogm to be sent */
 277 static unsigned long
 278 batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
 279 {
 280         unsigned int msecs;
 281
 282         msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
 283         msecs += prandom_u32_max(2 * BATADV_JITTER);
 284
 285         return jiffies + msecs_to_jiffies(msecs);
 286 }
 287
 288 /* when do we schedule a ogm packet to be sent */
 289 static unsigned long batadv_iv_ogm_fwd_send_time(void)
 290 {
 291         return jiffies + msecs_to_jiffies(prandom_u32_max(BATADV_JITTER / 2));
 292 }
 293
 294 /* apply hop penalty for a normal link */
 295 static u8 batadv_hop_penalty(u8 tq, const struct batadv_priv *bat_priv)
 296 {
 297         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
 298         int new_tq;
 299
 300         new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty);
 301         new_tq /= BATADV_TQ_MAX_VALUE;
 302
 303         return new_tq;
 304 }
 305
 306 /**
 307  * batadv_iv_ogm_aggr_packet() - checks if there is another OGM attached
 308  * @buff_pos: current position in the skb
 309  * @packet_len: total length of the skb
 310  * @ogm_packet: potential OGM in buffer
 311  *
 312  * Return: true if there is enough space for another OGM, false otherwise.
 313  */
 314 static bool
 315 batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
 316                           const struct batadv_ogm_packet *ogm_packet)
 317 {
 318         int next_buff_pos = 0;
 319
 320         /* check if there is enough space for the header */
 321         next_buff_pos += buff_pos + sizeof(*ogm_packet);
 322         if (next_buff_pos > packet_len)
 323                 return false;
 324
 325         /* check if there is enough space for the optional TVLV */
 326         next_buff_pos += ntohs(ogm_packet->tvlv_len);
 327
 328         return (next_buff_pos <= packet_len) &&
 329                (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
 330 }
 331
 332 /* send a batman ogm to a given interface */
 333 static void batadv_iv_ogm_send_to_if(struct batadv_forw_packet *forw_packet,
 334                                      struct batadv_hard_iface *hard_iface)
 335 {
 336         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 337         const char *fwd_str;
 338         u8 packet_num;
 339         s16 buff_pos;
 340         struct batadv_ogm_packet *batadv_ogm_packet;
 341         struct sk_buff *skb;
 342         u8 *packet_pos;
 343
 344         if (hard_iface->if_status != BATADV_IF_ACTIVE)
 345                 return;
 346
 347         packet_num = 0;
 348         buff_pos = 0;
 349         packet_pos = forw_packet->skb->data;
 350         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 351
 352         /* adjust all flags and log packets */
 353         while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
 354                                          batadv_ogm_packet)) {
 355                 /* we might have aggregated direct link packets with an
 356                  * ordinary base packet
 357                  */
 358                 if (forw_packet->direct_link_flags & BIT(packet_num) &&
 359                     forw_packet->if_incoming == hard_iface)
 360                         batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 361                 else
 362                         batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 363
 364                 if (packet_num > 0 || !forw_packet->own)
 365                         fwd_str = "Forwarding";
 366                 else
 367                         fwd_str = "Sending own";
 368
 369                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 370                            "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s) on interface %s [%pM]\n",
 371                            fwd_str, (packet_num > 0 ? "aggregated " : ""),
 372                            batadv_ogm_packet->orig,
 373                            ntohl(batadv_ogm_packet->seqno),
 374                            batadv_ogm_packet->tq, batadv_ogm_packet->ttl,
 375                            ((batadv_ogm_packet->flags & BATADV_DIRECTLINK) ?
 376                             "on" : "off"),
 377                            hard_iface->net_dev->name,
 378                            hard_iface->net_dev->dev_addr);
 379
 380                 buff_pos += BATADV_OGM_HLEN;
 381                 buff_pos += ntohs(batadv_ogm_packet->tvlv_len);
 382                 packet_num++;
 383                 packet_pos = forw_packet->skb->data + buff_pos;
 384                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 385         }
 386
 387         /* create clone because function is called more than once */
 388         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
 389         if (skb) {
 390                 batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
 391                 batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
 392                                    skb->len + ETH_HLEN);
 393                 batadv_send_broadcast_skb(skb, hard_iface);
 394         }
 395 }
 396
 397 /* send a batman ogm packet */
 398 static void batadv_iv_ogm_emit(struct batadv_forw_packet *forw_packet)
 399 {
 400         struct net_device *soft_iface;
 401
 402         if (!forw_packet->if_incoming) {
 403                 pr_err("Error - can't forward packet: incoming iface not specified\n");
 404                 return;
 405         }
 406
 407         soft_iface = forw_packet->if_incoming->soft_iface;
 408
 409         if (WARN_ON(!forw_packet->if_outgoing))
 410                 return;
 411
 412         if (WARN_ON(forw_packet->if_outgoing->soft_iface != soft_iface))
 413                 return;
 414
 415         if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE)
 416                 return;
 417
 418         /* only for one specific outgoing interface */
 419         batadv_iv_ogm_send_to_if(forw_packet, forw_packet->if_outgoing);
 420 }
 421
 422 /**
 423  * batadv_iv_ogm_can_aggregate() - find out if an OGM can be aggregated on an
 424  *  existing forward packet
 425  * @new_bat_ogm_packet: OGM packet to be aggregated
 426  * @bat_priv: the bat priv with all the soft interface information
 427  * @packet_len: (total) length of the OGM
 428  * @send_time: timestamp (jiffies) when the packet is to be sent
 429  * @directlink: true if this is a direct link packet
 430  * @if_incoming: interface where the packet was received
 431  * @if_outgoing: interface for which the retransmission should be considered
 432  * @forw_packet: the forwarded packet which should be checked
 433  *
 434  * Return: true if new_packet can be aggregated with forw_packet
 435  */
 436 static bool
 437 batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet,
 438                             struct batadv_priv *bat_priv,
 439                             int packet_len, unsigned long send_time,
 440                             bool directlink,
 441                             const struct batadv_hard_iface *if_incoming,
 442                             const struct batadv_hard_iface *if_outgoing,
 443                             const struct batadv_forw_packet *forw_packet)
 444 {
 445         struct batadv_ogm_packet *batadv_ogm_packet;
 446         int aggregated_bytes = forw_packet->packet_len + packet_len;
 447         struct batadv_hard_iface *primary_if = NULL;
 448         bool res = false;
 449         unsigned long aggregation_end_time;
 450
 451         batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
 452         aggregation_end_time = send_time;
 453         aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 454
 455         /* we can aggregate the current packet to this aggregated packet
 456          * if:
 457          *
 458          * - the send time is within our MAX_AGGREGATION_MS time
 459          * - the resulting packet won't be bigger than
 460          *   MAX_AGGREGATION_BYTES
 461          * otherwise aggregation is not possible
 462          */
 463         if (!time_before(send_time, forw_packet->send_time) ||
 464             !time_after_eq(aggregation_end_time, forw_packet->send_time))
 465                 return false;
 466
 467         if (aggregated_bytes > BATADV_MAX_AGGREGATION_BYTES)
 468                 return false;
 469
 470         /* packet is not leaving on the same interface. */
 471         if (forw_packet->if_outgoing != if_outgoing)
 472                 return false;
 473
 474         /* check aggregation compatibility
 475          * -> direct link packets are broadcasted on
 476          *    their interface only
 477          * -> aggregate packet if the current packet is
 478          *    a "global" packet as well as the base
 479          *    packet
 480          */
 481         primary_if = batadv_primary_if_get_selected(bat_priv);
 482         if (!primary_if)
 483                 return false;
 484
 485         /* packets without direct link flag and high TTL
 486          * are flooded through the net
 487          */
 488         if (!directlink &&
 489             !(batadv_ogm_packet->flags & BATADV_DIRECTLINK) &&
 490             batadv_ogm_packet->ttl != 1 &&
 491
 492             /* own packets originating non-primary
 493              * interfaces leave only that interface
 494              */
 495             (!forw_packet->own ||
 496              forw_packet->if_incoming == primary_if)) {
 497                 res = true;
 498                 goto out;
 499         }
 500
 501         /* if the incoming packet is sent via this one
 502          * interface only - we still can aggregate
 503          */
 504         if (directlink &&
 505             new_bat_ogm_packet->ttl == 1 &&
 506             forw_packet->if_incoming == if_incoming &&
 507
 508             /* packets from direct neighbors or
 509              * own secondary interface packets
 510              * (= secondary interface packets in general)
 511              */
 512             (batadv_ogm_packet->flags & BATADV_DIRECTLINK ||
 513              (forw_packet->own &&
 514               forw_packet->if_incoming != primary_if))) {
 515                 res = true;
 516                 goto out;
 517         }
 518
 519 out:
 520         if (primary_if)
 521                 batadv_hardif_put(primary_if);
 522         return res;
 523 }
 524
 525 /**
 526  * batadv_iv_ogm_aggregate_new() - create a new aggregated packet and add this
 527  *  packet to it.
 528  * @packet_buff: pointer to the OGM
 529  * @packet_len: (total) length of the OGM
 530  * @send_time: timestamp (jiffies) when the packet is to be sent
 531  * @direct_link: whether this OGM has direct link status
 532  * @if_incoming: interface where the packet was received
 533  * @if_outgoing: interface for which the retransmission should be considered
 534  * @own_packet: true if it is a self-generated ogm
 535  */
 536 static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 537                                         int packet_len, unsigned long send_time,
 538                                         bool direct_link,
 539                                         struct batadv_hard_iface *if_incoming,
 540                                         struct batadv_hard_iface *if_outgoing,
 541                                         int own_packet)
 542 {
 543         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 544         struct batadv_forw_packet *forw_packet_aggr;
 545         struct sk_buff *skb;
 546         unsigned char *skb_buff;
 547         unsigned int skb_size;
 548         atomic_t *queue_left = own_packet ? NULL : &bat_priv->batman_queue_left;
 549
 550         if (atomic_read(&bat_priv->aggregated_ogms) &&
 551             packet_len < BATADV_MAX_AGGREGATION_BYTES)
 552                 skb_size = BATADV_MAX_AGGREGATION_BYTES;
 553         else
 554                 skb_size = packet_len;
 555
 556         skb_size += ETH_HLEN;
 557
 558         skb = netdev_alloc_skb_ip_align(NULL, skb_size);
 559         if (!skb)
 560                 return;
 561
 562         forw_packet_aggr = batadv_forw_packet_alloc(if_incoming, if_outgoing,
 563                                                     queue_left, bat_priv, skb);
 564         if (!forw_packet_aggr) {
 565                 kfree_skb(skb);
 566                 return;
 567         }
 568
 569         forw_packet_aggr->skb->priority = TC_PRIO_CONTROL;
 570         skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
 571
 572         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 573         forw_packet_aggr->packet_len = packet_len;
 574         memcpy(skb_buff, packet_buff, packet_len);
 575
 576         forw_packet_aggr->own = own_packet;
 577         forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
 578         forw_packet_aggr->send_time = send_time;
 579
 580         /* save packet direct link flag status */
 581         if (direct_link)
 582                 forw_packet_aggr->direct_link_flags |= 1;
 583
 584         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 585                           batadv_iv_send_outstanding_bat_ogm_packet);
 586
 587         batadv_forw_packet_ogmv1_queue(bat_priv, forw_packet_aggr, send_time);
 588 }
 589
 590 /* aggregate a new packet into the existing ogm packet */
 591 static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr,
 592                                     const unsigned char *packet_buff,
 593                                     int packet_len, bool direct_link)
 594 {
 595         unsigned long new_direct_link_flag;
 596
 597         skb_put_data(forw_packet_aggr->skb, packet_buff, packet_len);
 598         forw_packet_aggr->packet_len += packet_len;
 599         forw_packet_aggr->num_packets++;
 600
 601         /* save packet direct link flag status */
 602         if (direct_link) {
 603                 new_direct_link_flag = BIT(forw_packet_aggr->num_packets);
 604                 forw_packet_aggr->direct_link_flags |= new_direct_link_flag;
 605         }
 606 }
 607
 608 /**
 609  * batadv_iv_ogm_queue_add() - queue up an OGM for transmission
 610  * @bat_priv: the bat priv with all the soft interface information
 611  * @packet_buff: pointer to the OGM
 612  * @packet_len: (total) length of the OGM
 613  * @if_incoming: interface where the packet was received
 614  * @if_outgoing: interface for which the retransmission should be considered
 615  * @own_packet: true if it is a self-generated ogm
 616  * @send_time: timestamp (jiffies) when the packet is to be sent
 617  */
 618 static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv,
 619                                     unsigned char *packet_buff,
 620                                     int packet_len,
 621                                     struct batadv_hard_iface *if_incoming,
 622                                     struct batadv_hard_iface *if_outgoing,
 623                                     int own_packet, unsigned long send_time)
 624 {
 625         /* _aggr -> pointer to the packet we want to aggregate with
 626          * _pos -> pointer to the position in the queue
 627          */
 628         struct batadv_forw_packet *forw_packet_aggr = NULL;
 629         struct batadv_forw_packet *forw_packet_pos = NULL;
 630         struct batadv_ogm_packet *batadv_ogm_packet;
 631         bool direct_link;
 632         unsigned long max_aggregation_jiffies;
 633
 634         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
 635         direct_link = !!(batadv_ogm_packet->flags & BATADV_DIRECTLINK);
 636         max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 637
 638         /* find position for the packet in the forward queue */
 639         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 640         /* own packets are not to be aggregated */
 641         if (atomic_read(&bat_priv->aggregated_ogms) && !own_packet) {
 642                 hlist_for_each_entry(forw_packet_pos,
 643                                      &bat_priv->forw_bat_list, list) {
 644                         if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet,
 645                                                         bat_priv, packet_len,
 646                                                         send_time, direct_link,
 647                                                         if_incoming,
 648                                                         if_outgoing,
 649                                                         forw_packet_pos)) {
 650                                 forw_packet_aggr = forw_packet_pos;
 651                                 break;
 652                         }
 653                 }
 654         }
 655
 656         /* nothing to aggregate with - either aggregation disabled or no
 657          * suitable aggregation packet found
 658          */
 659         if (!forw_packet_aggr) {
 660                 /* the following section can run without the lock */
 661                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 662
 663                 /* if we could not aggregate this packet with one of the others
 664                  * we hold it back for a while, so that it might be aggregated
 665                  * later on
 666                  */
 667                 if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
 668                         send_time += max_aggregation_jiffies;
 669
 670                 batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
 671                                             send_time, direct_link,
 672                                             if_incoming, if_outgoing,
 673                                             own_packet);
 674         } else {
 675                 batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 676                                         packet_len, direct_link);
 677                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 678         }
 679 }
 680
 681 static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
 682                                   const struct ethhdr *ethhdr,
 683                                   struct batadv_ogm_packet *batadv_ogm_packet,
 684                                   bool is_single_hop_neigh,
 685                                   bool is_from_best_next_hop,
 686                                   struct batadv_hard_iface *if_incoming,
 687                                   struct batadv_hard_iface *if_outgoing)
 688 {
 689         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 690         u16 tvlv_len;
 691
 692         if (batadv_ogm_packet->ttl <= 1) {
 693                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
 694                 return;
 695         }
 696
 697         if (!is_from_best_next_hop) {
 698                 /* Mark the forwarded packet when it is not coming from our
 699                  * best next hop. We still need to forward the packet for our
 700                  * neighbor link quality detection to work in case the packet
 701                  * originated from a single hop neighbor. Otherwise we can
 702                  * simply drop the ogm.
 703                  */
 704                 if (is_single_hop_neigh)
 705                         batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP;
 706                 else
 707                         return;
 708         }
 709
 710         tvlv_len = ntohs(batadv_ogm_packet->tvlv_len);
 711
 712         batadv_ogm_packet->ttl--;
 713         ether_addr_copy(batadv_ogm_packet->prev_sender, ethhdr->h_source);
 714
 715         /* apply hop penalty */
 716         batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq,
 717                                                    bat_priv);
 718
 719         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 720                    "Forwarding packet: tq: %i, ttl: %i\n",
 721                    batadv_ogm_packet->tq, batadv_ogm_packet->ttl);
 722
 723         if (is_single_hop_neigh)
 724                 batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 725         else
 726                 batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 727
 728         batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
 729                                 BATADV_OGM_HLEN + tvlv_len,
 730                                 if_incoming, if_outgoing, 0,
 731                                 batadv_iv_ogm_fwd_send_time());
 732 }
 733
 734 /**
 735  * batadv_iv_ogm_slide_own_bcast_window() - bitshift own OGM broadcast windows
 736  *  for the given interface
 737  * @hard_iface: the interface for which the windows have to be shifted
 738  */
 739 static void
 740 batadv_iv_ogm_slide_own_bcast_window(struct batadv_hard_iface *hard_iface)
 741 {
 742         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 743         struct batadv_hashtable *hash = bat_priv->orig_hash;
 744         struct hlist_head *head;
 745         struct batadv_orig_node *orig_node;
 746         struct batadv_orig_ifinfo *orig_ifinfo;
 747         unsigned long *word;
 748         u32 i;
 749         u8 *w;
 750
 751         for (i = 0; i < hash->size; i++) {
 752                 head = &hash->table[i];
 753
 754                 rcu_read_lock();
 755                 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
 756                         hlist_for_each_entry_rcu(orig_ifinfo,
 757                                                  &orig_node->ifinfo_list,
 758                                                  list) {
 759                                 if (orig_ifinfo->if_outgoing != hard_iface)
 760                                         continue;
 761
 762                                 spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 763                                 word = orig_ifinfo->bat_iv.bcast_own;
 764                                 batadv_bit_get_packet(bat_priv, word, 1, 0);
 765                                 w = &orig_ifinfo->bat_iv.bcast_own_sum;
 766                                 *w = bitmap_weight(word,
 767                                                    BATADV_TQ_LOCAL_WINDOW_SIZE);
 768                                 spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 769                         }
 770                 }
 771                 rcu_read_unlock();
 772         }
 773 }
 774
 775 /**
 776  * batadv_iv_ogm_schedule_buff() - schedule submission of hardif ogm buffer
 777  * @hard_iface: interface whose ogm buffer should be transmitted
 778  */
 779 static void batadv_iv_ogm_schedule_buff(struct batadv_hard_iface *hard_iface)
 780 {
 781         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 782         unsigned char **ogm_buff = &hard_iface->bat_iv.ogm_buff;
 783         struct batadv_ogm_packet *batadv_ogm_packet;
 784         struct batadv_hard_iface *primary_if, *tmp_hard_iface;
 785         int *ogm_buff_len = &hard_iface->bat_iv.ogm_buff_len;
 786         u32 seqno;
 787         u16 tvlv_len = 0;
 788         unsigned long send_time;
 789
 790         lockdep_assert_held(&hard_iface->bat_iv.ogm_buff_mutex);
 791
 792         /* interface already disabled by batadv_iv_ogm_iface_disable */
 793         if (!*ogm_buff)
 794                 return;
 795
 796         /* the interface gets activated here to avoid race conditions between
 797          * the moment of activating the interface in
 798          * hardif_activate_interface() where the originator mac is set and
 799          * outdated packets (especially uninitialized mac addresses) in the
 800          * packet queue
 801          */
 802         if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED)
 803                 hard_iface->if_status = BATADV_IF_ACTIVE;
 804
 805         primary_if = batadv_primary_if_get_selected(bat_priv);
 806
 807         if (hard_iface == primary_if) {
 808                 /* tt changes have to be committed before the tvlv data is
 809                  * appended as it may alter the tt tvlv container
 810                  */
 811                 batadv_tt_local_commit_changes(bat_priv);
 812                 tvlv_len = batadv_tvlv_container_ogm_append(bat_priv, ogm_buff,
 813                                                             ogm_buff_len,
 814                                                             BATADV_OGM_HLEN);
 815         }
 816
 817         batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff);
 818         batadv_ogm_packet->tvlv_len = htons(tvlv_len);
 819
 820         /* change sequence number to network order */
 821         seqno = (u32)atomic_read(&hard_iface->bat_iv.ogm_seqno);
 822         batadv_ogm_packet->seqno = htonl(seqno);
 823         atomic_inc(&hard_iface->bat_iv.ogm_seqno);
 824
 825         batadv_iv_ogm_slide_own_bcast_window(hard_iface);
 826
 827         send_time = batadv_iv_ogm_emit_send_time(bat_priv);
 828
 829         if (hard_iface != primary_if) {
 830                 /* OGMs from secondary interfaces are only scheduled on their
 831                  * respective interfaces.
 832                  */
 833                 batadv_iv_ogm_queue_add(bat_priv, *ogm_buff, *ogm_buff_len,
 834                                         hard_iface, hard_iface, 1, send_time);
 835                 goto out;
 836         }
 837
 838         /* OGMs from primary interfaces are scheduled on all
 839          * interfaces.
 840          */
 841         rcu_read_lock();
 842         list_for_each_entry_rcu(tmp_hard_iface, &batadv_hardif_list, list) {
 843                 if (tmp_hard_iface->soft_iface != hard_iface->soft_iface)
 844                         continue;
 845
 846                 if (!kref_get_unless_zero(&tmp_hard_iface->refcount))
 847                         continue;
 848
 849                 batadv_iv_ogm_queue_add(bat_priv, *ogm_buff,
 850                                         *ogm_buff_len, hard_iface,
 851                                         tmp_hard_iface, 1, send_time);
 852
 853                 batadv_hardif_put(tmp_hard_iface);
 854         }
 855         rcu_read_unlock();
 856
 857 out:
 858         if (primary_if)
 859                 batadv_hardif_put(primary_if);
 860 }
 861
 862 static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
 863 {
 864         if (hard_iface->if_status == BATADV_IF_NOT_IN_USE ||
 865             hard_iface->if_status == BATADV_IF_TO_BE_REMOVED)
 866                 return;
 867
 868         mutex_lock(&hard_iface->bat_iv.ogm_buff_mutex);
 869         batadv_iv_ogm_schedule_buff(hard_iface);
 870         mutex_unlock(&hard_iface->bat_iv.ogm_buff_mutex);
 871 }
 872
 873 /**
 874  * batadv_iv_orig_ifinfo_sum() - Get bcast_own sum for originator over interface
 875  * @orig_node: originator which reproadcasted the OGMs directly
 876  * @if_outgoing: interface which transmitted the original OGM and received the
 877  *  direct rebroadcast
 878  *
 879  * Return: Number of replied (rebroadcasted) OGMs which were transmitted by
 880  *  an originator and directly (without intermediate hop) received by a specific
 881  *  interface
 882  */
 883 static u8 batadv_iv_orig_ifinfo_sum(struct batadv_orig_node *orig_node,
 884                                     struct batadv_hard_iface *if_outgoing)
 885 {
 886         struct batadv_orig_ifinfo *orig_ifinfo;
 887         u8 sum;
 888
 889         orig_ifinfo = batadv_orig_ifinfo_get(orig_node, if_outgoing);
 890         if (!orig_ifinfo)
 891                 return 0;
 892
 893         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 894         sum = orig_ifinfo->bat_iv.bcast_own_sum;
 895         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 896
 897         batadv_orig_ifinfo_put(orig_ifinfo);
 898
 899         return sum;
 900 }
 901
 902 /**
 903  * batadv_iv_ogm_orig_update() - use OGM to update corresponding data in an
 904  *  originator
 905  * @bat_priv: the bat priv with all the soft interface information
 906  * @orig_node: the orig node who originally emitted the ogm packet
 907  * @orig_ifinfo: ifinfo for the outgoing interface of the orig_node
 908  * @ethhdr: Ethernet header of the OGM
 909  * @batadv_ogm_packet: the ogm packet
 910  * @if_incoming: interface where the packet was received
 911  * @if_outgoing: interface for which the retransmission should be considered
 912  * @dup_status: the duplicate status of this ogm packet.
 913  */
 914 static void
 915 batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv,
 916                           struct batadv_orig_node *orig_node,
 917                           struct batadv_orig_ifinfo *orig_ifinfo,
 918                           const struct ethhdr *ethhdr,
 919                           const struct batadv_ogm_packet *batadv_ogm_packet,
 920                           struct batadv_hard_iface *if_incoming,
 921                           struct batadv_hard_iface *if_outgoing,
 922                           enum batadv_dup_status dup_status)
 923 {
 924         struct batadv_neigh_ifinfo *neigh_ifinfo = NULL;
 925         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
 926         struct batadv_neigh_node *neigh_node = NULL;
 927         struct batadv_neigh_node *tmp_neigh_node = NULL;
 928         struct batadv_neigh_node *router = NULL;
 929         u8 sum_orig, sum_neigh;
 930         u8 *neigh_addr;
 931         u8 tq_avg;
 932
 933         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 934                    "%s(): Searching and updating originator entry of received packet\n",
 935                    __func__);
 936
 937         rcu_read_lock();
 938         hlist_for_each_entry_rcu(tmp_neigh_node,
 939                                  &orig_node->neigh_list, list) {
 940                 neigh_addr = tmp_neigh_node->addr;
 941                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 942                     tmp_neigh_node->if_incoming == if_incoming &&
 943                     kref_get_unless_zero(&tmp_neigh_node->refcount)) {
 944                         if (WARN(neigh_node, "too many matching neigh_nodes"))
 945                                 batadv_neigh_node_put(neigh_node);
 946                         neigh_node = tmp_neigh_node;
 947                         continue;
 948                 }
 949
 950                 if (dup_status != BATADV_NO_DUP)
 951                         continue;
 952
 953                 /* only update the entry for this outgoing interface */
 954                 neigh_ifinfo = batadv_neigh_ifinfo_get(tmp_neigh_node,
 955                                                        if_outgoing);
 956                 if (!neigh_ifinfo)
 957                         continue;
 958
 959                 spin_lock_bh(&tmp_neigh_node->ifinfo_lock);
 960                 batadv_ring_buffer_set(neigh_ifinfo->bat_iv.tq_recv,
 961                                        &neigh_ifinfo->bat_iv.tq_index, 0);
 962                 tq_avg = batadv_ring_buffer_avg(neigh_ifinfo->bat_iv.tq_recv);
 963                 neigh_ifinfo->bat_iv.tq_avg = tq_avg;
 964                 spin_unlock_bh(&tmp_neigh_node->ifinfo_lock);
 965
 966                 batadv_neigh_ifinfo_put(neigh_ifinfo);
 967                 neigh_ifinfo = NULL;
 968         }
 969
 970         if (!neigh_node) {
 971                 struct batadv_orig_node *orig_tmp;
 972
 973                 orig_tmp = batadv_iv_ogm_orig_get(bat_priv, ethhdr->h_source);
 974                 if (!orig_tmp)
 975                         goto unlock;
 976
 977                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 978                                                      ethhdr->h_source,
 979                                                      orig_node, orig_tmp);
 980
 981                 batadv_orig_node_put(orig_tmp);
 982                 if (!neigh_node)
 983                         goto unlock;
 984         } else {
 985                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 986                            "Updating existing last-hop neighbor of originator\n");
 987         }
 988
 989         rcu_read_unlock();
 990         neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing);
 991         if (!neigh_ifinfo)
 992                 goto out;
 993
 994         neigh_node->last_seen = jiffies;
 995
 996         spin_lock_bh(&neigh_node->ifinfo_lock);
 997         batadv_ring_buffer_set(neigh_ifinfo->bat_iv.tq_recv,
 998                                &neigh_ifinfo->bat_iv.tq_index,
 999                                batadv_ogm_packet->tq);
1000         tq_avg = batadv_ring_buffer_avg(neigh_ifinfo->bat_iv.tq_recv);
1001         neigh_ifinfo->bat_iv.tq_avg = tq_avg;
1002         spin_unlock_bh(&neigh_node->ifinfo_lock);
1003
1004         if (dup_status == BATADV_NO_DUP) {
1005                 orig_ifinfo->last_ttl = batadv_ogm_packet->ttl;
1006                 neigh_ifinfo->last_ttl = batadv_ogm_packet->ttl;
1007         }
1008
1009         /* if this neighbor already is our next hop there is nothing
1010          * to change
1011          */
1012         router = batadv_orig_router_get(orig_node, if_outgoing);
1013         if (router == neigh_node)
1014                 goto out;
1015
1016         if (router) {
1017                 router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing);
1018                 if (!router_ifinfo)
1019                         goto out;
1020
1021                 /* if this neighbor does not offer a better TQ we won't
1022                  * consider it
1023                  */
1024                 if (router_ifinfo->bat_iv.tq_avg > neigh_ifinfo->bat_iv.tq_avg)
1025                         goto out;
1026         }
1027
1028         /* if the TQ is the same and the link not more symmetric we
1029          * won't consider it either
1030          */
1031         if (router_ifinfo &&
1032             neigh_ifinfo->bat_iv.tq_avg == router_ifinfo->bat_iv.tq_avg) {
1033                 sum_orig = batadv_iv_orig_ifinfo_sum(router->orig_node,
1034                                                      router->if_incoming);
1035                 sum_neigh = batadv_iv_orig_ifinfo_sum(neigh_node->orig_node,
1036                                                       neigh_node->if_incoming);
1037                 if (sum_orig >= sum_neigh)
1038                         goto out;
1039         }
1040
1041         batadv_update_route(bat_priv, orig_node, if_outgoing, neigh_node);
1042         goto out;
1043
1044 unlock:
1045         rcu_read_unlock();
1046 out:
1047         if (neigh_node)
1048                 batadv_neigh_node_put(neigh_node);
1049         if (router)
1050                 batadv_neigh_node_put(router);
1051         if (neigh_ifinfo)
1052                 batadv_neigh_ifinfo_put(neigh_ifinfo);
1053         if (router_ifinfo)
1054                 batadv_neigh_ifinfo_put(router_ifinfo);
1055 }
1056
1057 /**
1058  * batadv_iv_ogm_calc_tq() - calculate tq for current received ogm packet
1059  * @orig_node: the orig node who originally emitted the ogm packet
1060  * @orig_neigh_node: the orig node struct of the neighbor who sent the packet
1061  * @batadv_ogm_packet: the ogm packet
1062  * @if_incoming: interface where the packet was received
1063  * @if_outgoing: interface for which the retransmission should be considered
1064  *
1065  * Return: true if the link can be considered bidirectional, false otherwise
1066  */
1067 static bool batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
1068                                   struct batadv_orig_node *orig_neigh_node,
1069                                   struct batadv_ogm_packet *batadv_ogm_packet,
1070                                   struct batadv_hard_iface *if_incoming,
1071                                   struct batadv_hard_iface *if_outgoing)
1072 {
1073         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1074         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node;
1075         struct batadv_neigh_ifinfo *neigh_ifinfo;
1076         u8 total_count;
1077         u8 orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
1078         unsigned int tq_iface_hop_penalty = BATADV_TQ_MAX_VALUE;
1079         unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
1080         unsigned int tq_asym_penalty, inv_asym_penalty;
1081         unsigned int combined_tq;
1082         bool ret = false;
1083
1084         /* find corresponding one hop neighbor */
1085         rcu_read_lock();
1086         hlist_for_each_entry_rcu(tmp_neigh_node,
1087                                  &orig_neigh_node->neigh_list, list) {
1088                 if (!batadv_compare_eth(tmp_neigh_node->addr,
1089                                         orig_neigh_node->orig))
1090                         continue;
1091
1092                 if (tmp_neigh_node->if_incoming != if_incoming)
1093                         continue;
1094
1095                 if (!kref_get_unless_zero(&tmp_neigh_node->refcount))
1096                         continue;
1097
1098                 neigh_node = tmp_neigh_node;
1099                 break;
1100         }
1101         rcu_read_unlock();
1102
1103         if (!neigh_node)
1104                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
1105                                                      orig_neigh_node->orig,
1106                                                      orig_neigh_node,
1107                                                      orig_neigh_node);
1108
1109         if (!neigh_node)
1110                 goto out;
1111
1112         /* if orig_node is direct neighbor update neigh_node last_seen */
1113         if (orig_node == orig_neigh_node)
1114                 neigh_node->last_seen = jiffies;
1115
1116         orig_node->last_seen = jiffies;
1117
1118         /* find packet count of corresponding one hop neighbor */
1119         orig_eq_count = batadv_iv_orig_ifinfo_sum(orig_neigh_node, if_incoming);
1120         neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing);
1121         if (neigh_ifinfo) {
1122                 neigh_rq_count = neigh_ifinfo->bat_iv.real_packet_count;
1123                 batadv_neigh_ifinfo_put(neigh_ifinfo);
1124         } else {
1125                 neigh_rq_count = 0;
1126         }
1127
1128         /* pay attention to not get a value bigger than 100 % */
1129         if (orig_eq_count > neigh_rq_count)
1130                 total_count = neigh_rq_count;
1131         else
1132                 total_count = orig_eq_count;
1133
1134         /* if we have too few packets (too less data) we set tq_own to zero
1135          * if we receive too few packets it is not considered bidirectional
1136          */
1137         if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
1138             neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
1139                 tq_own = 0;
1140         else
1141                 /* neigh_node->real_packet_count is never zero as we
1142                  * only purge old information when getting new
1143                  * information
1144                  */
1145                 tq_own = (BATADV_TQ_MAX_VALUE * total_count) /  neigh_rq_count;
1146
1147         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
1148          * affect the nearly-symmetric links only a little, but
1149          * punishes asymmetric links more.  This will give a value
1150          * between 0 and TQ_MAX_VALUE
1151          */
1152         neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
1153         neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
1154         neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
1155                             BATADV_TQ_LOCAL_WINDOW_SIZE *
1156                             BATADV_TQ_LOCAL_WINDOW_SIZE;
1157         inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
1158         inv_asym_penalty /= neigh_rq_max_cube;
1159         tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;
1160         tq_iface_hop_penalty -= atomic_read(&if_incoming->hop_penalty);
1161
1162         /* penalize if the OGM is forwarded on the same interface. WiFi
1163          * interfaces and other half duplex devices suffer from throughput
1164          * drops as they can't send and receive at the same time.
1165          */
1166         if (if_outgoing && if_incoming == if_outgoing &&
1167             batadv_is_wifi_hardif(if_outgoing))
1168                 tq_iface_hop_penalty = batadv_hop_penalty(tq_iface_hop_penalty,
1169                                                           bat_priv);
1170
1171         combined_tq = batadv_ogm_packet->tq *
1172                       tq_own *
1173                       tq_asym_penalty *
1174                       tq_iface_hop_penalty;
1175         combined_tq /= BATADV_TQ_MAX_VALUE *
1176                        BATADV_TQ_MAX_VALUE *
1177                        BATADV_TQ_MAX_VALUE;
1178         batadv_ogm_packet->tq = combined_tq;
1179
1180         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1181                    "bidirectional: orig = %pM neigh = %pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, iface_hop_penalty: %3i, total tq: %3i, if_incoming = %s, if_outgoing = %s\n",
1182                    orig_node->orig, orig_neigh_node->orig, total_count,
1183                    neigh_rq_count, tq_own, tq_asym_penalty,
1184                    tq_iface_hop_penalty, batadv_ogm_packet->tq,
1185                    if_incoming->net_dev->name,
1186                    if_outgoing ? if_outgoing->net_dev->name : "DEFAULT");
1187
1188         /* if link has the minimum required transmission quality
1189          * consider it bidirectional
1190          */
1191         if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
1192                 ret = true;
1193
1194 out:
1195         if (neigh_node)
1196                 batadv_neigh_node_put(neigh_node);
1197         return ret;
1198 }
1199
1200 /**
1201  * batadv_iv_ogm_update_seqnos() -  process a batman packet for all interfaces,
1202  *  adjust the sequence number and find out whether it is a duplicate
1203  * @ethhdr: ethernet header of the packet
1204  * @batadv_ogm_packet: OGM packet to be considered
1205  * @if_incoming: interface on which the OGM packet was received
1206  * @if_outgoing: interface for which the retransmission should be considered
1207  *
1208  * Return: duplicate status as enum batadv_dup_status
1209  */
1210 static enum batadv_dup_status
1211 batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
1212                             const struct batadv_ogm_packet *batadv_ogm_packet,
1213                             const struct batadv_hard_iface *if_incoming,
1214                             struct batadv_hard_iface *if_outgoing)
1215 {
1216         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1217         struct batadv_orig_node *orig_node;
1218         struct batadv_orig_ifinfo *orig_ifinfo = NULL;
1219         struct batadv_neigh_node *neigh_node;
1220         struct batadv_neigh_ifinfo *neigh_ifinfo;
1221         bool is_dup;
1222         s32 seq_diff;
1223         bool need_update = false;
1224         int set_mark;
1225         enum batadv_dup_status ret = BATADV_NO_DUP;
1226         u32 seqno = ntohl(batadv_ogm_packet->seqno);
1227         u8 *neigh_addr;
1228         u8 packet_count;
1229         unsigned long *bitmap;
1230
1231         orig_node = batadv_iv_ogm_orig_get(bat_priv, batadv_ogm_packet->orig);
1232         if (!orig_node)
1233                 return BATADV_NO_DUP;
1234
1235         orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
1236         if (WARN_ON(!orig_ifinfo)) {
1237                 batadv_orig_node_put(orig_node);
1238                 return 0;
1239         }
1240
1241         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1242         seq_diff = seqno - orig_ifinfo->last_real_seqno;
1243
1244         /* signalize caller that the packet is to be dropped. */
1245         if (!hlist_empty(&orig_node->neigh_list) &&
1246             batadv_window_protected(bat_priv, seq_diff,
1247                                     BATADV_TQ_LOCAL_WINDOW_SIZE,
1248                                     &orig_ifinfo->batman_seqno_reset, NULL)) {
1249                 ret = BATADV_PROTECTED;
1250                 goto out;
1251         }
1252
1253         rcu_read_lock();
1254         hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
1255                 neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node,
1256                                                        if_outgoing);
1257                 if (!neigh_ifinfo)
1258                         continue;
1259
1260                 neigh_addr = neigh_node->addr;
1261                 is_dup = batadv_test_bit(neigh_ifinfo->bat_iv.real_bits,
1262                                          orig_ifinfo->last_real_seqno,
1263                                          seqno);
1264
1265                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
1266                     neigh_node->if_incoming == if_incoming) {
1267                         set_mark = 1;
1268                         if (is_dup)
1269                                 ret = BATADV_NEIGH_DUP;
1270                 } else {
1271                         set_mark = 0;
1272                         if (is_dup && ret != BATADV_NEIGH_DUP)
1273                                 ret = BATADV_ORIG_DUP;
1274                 }
1275
1276                 /* if the window moved, set the update flag. */
1277                 bitmap = neigh_ifinfo->bat_iv.real_bits;
1278                 need_update |= batadv_bit_get_packet(bat_priv, bitmap,
1279                                                      seq_diff, set_mark);
1280
1281                 packet_count = bitmap_weight(bitmap,
1282                                              BATADV_TQ_LOCAL_WINDOW_SIZE);
1283                 neigh_ifinfo->bat_iv.real_packet_count = packet_count;
1284                 batadv_neigh_ifinfo_put(neigh_ifinfo);
1285         }
1286         rcu_read_unlock();
1287
1288         if (need_update) {
1289                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1290                            "%s updating last_seqno: old %u, new %u\n",
1291                            if_outgoing ? if_outgoing->net_dev->name : "DEFAULT",
1292                            orig_ifinfo->last_real_seqno, seqno);
1293                 orig_ifinfo->last_real_seqno = seqno;
1294         }
1295
1296 out:
1297         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1298         batadv_orig_node_put(orig_node);
1299         batadv_orig_ifinfo_put(orig_ifinfo);
1300         return ret;
1301 }
1302
1303 /**
1304  * batadv_iv_ogm_process_per_outif() - process a batman iv OGM for an outgoing
1305  *  interface
1306  * @skb: the skb containing the OGM
1307  * @ogm_offset: offset from skb->data to start of ogm header
1308  * @orig_node: the (cached) orig node for the originator of this OGM
1309  * @if_incoming: the interface where this packet was received
1310  * @if_outgoing: the interface for which the packet should be considered
1311  */
1312 static void
1313 batadv_iv_ogm_process_per_outif(const struct sk_buff *skb, int ogm_offset,
1314                                 struct batadv_orig_node *orig_node,
1315                                 struct batadv_hard_iface *if_incoming,
1316                                 struct batadv_hard_iface *if_outgoing)
1317 {
1318         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1319         struct batadv_hardif_neigh_node *hardif_neigh = NULL;
1320         struct batadv_neigh_node *router = NULL;
1321         struct batadv_neigh_node *router_router = NULL;
1322         struct batadv_orig_node *orig_neigh_node;
1323         struct batadv_orig_ifinfo *orig_ifinfo;
1324         struct batadv_neigh_node *orig_neigh_router = NULL;
1325         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
1326         struct batadv_ogm_packet *ogm_packet;
1327         enum batadv_dup_status dup_status;
1328         bool is_from_best_next_hop = false;
1329         bool is_single_hop_neigh = false;
1330         bool sameseq, similar_ttl;
1331         struct sk_buff *skb_priv;
1332         struct ethhdr *ethhdr;
1333         u8 *prev_sender;
1334         bool is_bidirect;
1335
1336         /* create a private copy of the skb, as some functions change tq value
1337          * and/or flags.
1338          */
1339         skb_priv = skb_copy(skb, GFP_ATOMIC);
1340         if (!skb_priv)
1341                 return;
1342
1343         ethhdr = eth_hdr(skb_priv);
1344         ogm_packet = (struct batadv_ogm_packet *)(skb_priv->data + ogm_offset);
1345
1346         dup_status = batadv_iv_ogm_update_seqnos(ethhdr, ogm_packet,
1347                                                  if_incoming, if_outgoing);
1348         if (batadv_compare_eth(ethhdr->h_source, ogm_packet->orig))
1349                 is_single_hop_neigh = true;
1350
1351         if (dup_status == BATADV_PROTECTED) {
1352                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1353                            "Drop packet: packet within seqno protection time (sender: %pM)\n",
1354                            ethhdr->h_source);
1355                 goto out;
1356         }
1357
1358         if (ogm_packet->tq == 0) {
1359                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1360                            "Drop packet: originator packet with tq equal 0\n");
1361                 goto out;
1362         }
1363
1364         if (is_single_hop_neigh) {
1365                 hardif_neigh = batadv_hardif_neigh_get(if_incoming,
1366                                                        ethhdr->h_source);
1367                 if (hardif_neigh)
1368                         hardif_neigh->last_seen = jiffies;
1369         }
1370
1371         router = batadv_orig_router_get(orig_node, if_outgoing);
1372         if (router) {
1373                 router_router = batadv_orig_router_get(router->orig_node,
1374                                                        if_outgoing);
1375                 router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing);
1376         }
1377
1378         if ((router_ifinfo && router_ifinfo->bat_iv.tq_avg != 0) &&
1379             (batadv_compare_eth(router->addr, ethhdr->h_source)))
1380                 is_from_best_next_hop = true;
1381
1382         prev_sender = ogm_packet->prev_sender;
1383         /* avoid temporary routing loops */
1384         if (router && router_router &&
1385             (batadv_compare_eth(router->addr, prev_sender)) &&
1386             !(batadv_compare_eth(ogm_packet->orig, prev_sender)) &&
1387             (batadv_compare_eth(router->addr, router_router->addr))) {
1388                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1389                            "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1390                            ethhdr->h_source);
1391                 goto out;
1392         }
1393
1394         if (if_outgoing == BATADV_IF_DEFAULT)
1395                 batadv_tvlv_ogm_receive(bat_priv, ogm_packet, orig_node);
1396
1397         /* if sender is a direct neighbor the sender mac equals
1398          * originator mac
1399          */
1400         if (is_single_hop_neigh)
1401                 orig_neigh_node = orig_node;
1402         else
1403                 orig_neigh_node = batadv_iv_ogm_orig_get(bat_priv,
1404                                                          ethhdr->h_source);
1405
1406         if (!orig_neigh_node)
1407                 goto out;
1408
1409         /* Update nc_nodes of the originator */
1410         batadv_nc_update_nc_node(bat_priv, orig_node, orig_neigh_node,
1411                                  ogm_packet, is_single_hop_neigh);
1412
1413         orig_neigh_router = batadv_orig_router_get(orig_neigh_node,
1414                                                    if_outgoing);
1415
1416         /* drop packet if sender is not a direct neighbor and if we
1417          * don't route towards it
1418          */
1419         if (!is_single_hop_neigh && !orig_neigh_router) {
1420                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1421                            "Drop packet: OGM via unknown neighbor!\n");
1422                 goto out_neigh;
1423         }
1424
1425         is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1426                                             ogm_packet, if_incoming,
1427                                             if_outgoing);
1428
1429         /* update ranking if it is not a duplicate or has the same
1430          * seqno and similar ttl as the non-duplicate
1431          */
1432         orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
1433         if (!orig_ifinfo)
1434                 goto out_neigh;
1435
1436         sameseq = orig_ifinfo->last_real_seqno == ntohl(ogm_packet->seqno);
1437         similar_ttl = (orig_ifinfo->last_ttl - 3) <= ogm_packet->ttl;
1438
1439         if (is_bidirect && (dup_status == BATADV_NO_DUP ||
1440                             (sameseq && similar_ttl))) {
1441                 batadv_iv_ogm_orig_update(bat_priv, orig_node,
1442                                           orig_ifinfo, ethhdr,
1443                                           ogm_packet, if_incoming,
1444                                           if_outgoing, dup_status);
1445         }
1446         batadv_orig_ifinfo_put(orig_ifinfo);
1447
1448         /* only forward for specific interface, not for the default one. */
1449         if (if_outgoing == BATADV_IF_DEFAULT)
1450                 goto out_neigh;
1451
1452         /* is single hop (direct) neighbor */
1453         if (is_single_hop_neigh) {
1454                 /* OGMs from secondary interfaces should only scheduled once
1455                  * per interface where it has been received, not multiple times
1456                  */
1457                 if (ogm_packet->ttl <= 2 &&
1458                     if_incoming != if_outgoing) {
1459                         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1460                                    "Drop packet: OGM from secondary interface and wrong outgoing interface\n");
1461                         goto out_neigh;
1462                 }
1463                 /* mark direct link on incoming interface */
1464                 batadv_iv_ogm_forward(orig_node, ethhdr, ogm_packet,
1465                                       is_single_hop_neigh,
1466                                       is_from_best_next_hop, if_incoming,
1467                                       if_outgoing);
1468
1469                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1470                            "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1471                 goto out_neigh;
1472         }
1473
1474         /* multihop originator */
1475         if (!is_bidirect) {
1476                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1477                            "Drop packet: not received via bidirectional link\n");
1478                 goto out_neigh;
1479         }
1480
1481         if (dup_status == BATADV_NEIGH_DUP) {
1482                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1483                            "Drop packet: duplicate packet received\n");
1484                 goto out_neigh;
1485         }
1486
1487         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1488                    "Forwarding packet: rebroadcast originator packet\n");
1489         batadv_iv_ogm_forward(orig_node, ethhdr, ogm_packet,
1490                               is_single_hop_neigh, is_from_best_next_hop,
1491                               if_incoming, if_outgoing);
1492
1493 out_neigh:
1494         if (orig_neigh_node && !is_single_hop_neigh)
1495                 batadv_orig_node_put(orig_neigh_node);
1496 out:
1497         if (router_ifinfo)
1498                 batadv_neigh_ifinfo_put(router_ifinfo);
1499         if (router)
1500                 batadv_neigh_node_put(router);
1501         if (router_router)
1502                 batadv_neigh_node_put(router_router);
1503         if (orig_neigh_router)
1504                 batadv_neigh_node_put(orig_neigh_router);
1505         if (hardif_neigh)
1506                 batadv_hardif_neigh_put(hardif_neigh);
1507
1508         consume_skb(skb_priv);
1509 }
1510
1511 /**
1512  * batadv_iv_ogm_process_reply() - Check OGM for direct reply and process it
1513  * @ogm_packet: rebroadcast OGM packet to process
1514  * @if_incoming: the interface where this packet was received
1515  * @orig_node: originator which reproadcasted the OGMs
1516  * @if_incoming_seqno: OGM sequence number when rebroadcast was received
1517  */
1518 static void batadv_iv_ogm_process_reply(struct batadv_ogm_packet *ogm_packet,
1519                                         struct batadv_hard_iface *if_incoming,
1520                                         struct batadv_orig_node *orig_node,
1521                                         u32 if_incoming_seqno)
1522 {
1523         struct batadv_orig_ifinfo *orig_ifinfo;
1524         s32 bit_pos;
1525         u8 *weight;
1526
1527         /* neighbor has to indicate direct link and it has to
1528          * come via the corresponding interface
1529          */
1530         if (!(ogm_packet->flags & BATADV_DIRECTLINK))
1531                 return;
1532
1533         if (!batadv_compare_eth(if_incoming->net_dev->dev_addr,
1534                                 ogm_packet->orig))
1535                 return;
1536
1537         orig_ifinfo = batadv_orig_ifinfo_get(orig_node, if_incoming);
1538         if (!orig_ifinfo)
1539                 return;
1540
1541         /* save packet seqno for bidirectional check */
1542         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1543         bit_pos = if_incoming_seqno - 2;
1544         bit_pos -= ntohl(ogm_packet->seqno);
1545         batadv_set_bit(orig_ifinfo->bat_iv.bcast_own, bit_pos);
1546         weight = &orig_ifinfo->bat_iv.bcast_own_sum;
1547         *weight = bitmap_weight(orig_ifinfo->bat_iv.bcast_own,
1548                                 BATADV_TQ_LOCAL_WINDOW_SIZE);
1549         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1550
1551         batadv_orig_ifinfo_put(orig_ifinfo);
1552 }
1553
1554 /**
1555  * batadv_iv_ogm_process() - process an incoming batman iv OGM
1556  * @skb: the skb containing the OGM
1557  * @ogm_offset: offset to the OGM which should be processed (for aggregates)
1558  * @if_incoming: the interface where this packet was received
1559  */
1560 static void batadv_iv_ogm_process(const struct sk_buff *skb, int ogm_offset,
1561                                   struct batadv_hard_iface *if_incoming)
1562 {
1563         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1564         struct batadv_orig_node *orig_neigh_node, *orig_node;
1565         struct batadv_hard_iface *hard_iface;
1566         struct batadv_ogm_packet *ogm_packet;
1567         u32 if_incoming_seqno;
1568         bool has_directlink_flag;
1569         struct ethhdr *ethhdr;
1570         bool is_my_oldorig = false;
1571         bool is_my_addr = false;
1572         bool is_my_orig = false;
1573
1574         ogm_packet = (struct batadv_ogm_packet *)(skb->data + ogm_offset);
1575         ethhdr = eth_hdr(skb);
1576
1577         /* Silently drop when the batman packet is actually not a
1578          * correct packet.
1579          *
1580          * This might happen if a packet is padded (e.g. Ethernet has a
1581          * minimum frame length of 64 byte) and the aggregation interprets
1582          * it as an additional length.
1583          *
1584          * TODO: A more sane solution would be to have a bit in the
1585          * batadv_ogm_packet to detect whether the packet is the last
1586          * packet in an aggregation.  Here we expect that the padding
1587          * is always zero (or not 0x01)
1588          */
1589         if (ogm_packet->packet_type != BATADV_IV_OGM)
1590                 return;
1591
1592         /* could be changed by schedule_own_packet() */
1593         if_incoming_seqno = atomic_read(&if_incoming->bat_iv.ogm_seqno);
1594
1595         if (ogm_packet->flags & BATADV_DIRECTLINK)
1596                 has_directlink_flag = true;
1597         else
1598                 has_directlink_flag = false;
1599
1600         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1601                    "Received BATMAN packet via NB: %pM, IF: %s [%pM] (from OG: %pM, via prev OG: %pM, seqno %u, tq %d, TTL %d, V %d, IDF %d)\n",
1602                    ethhdr->h_source, if_incoming->net_dev->name,
1603                    if_incoming->net_dev->dev_addr, ogm_packet->orig,
1604                    ogm_packet->prev_sender, ntohl(ogm_packet->seqno),
1605                    ogm_packet->tq, ogm_packet->ttl,
1606                    ogm_packet->version, has_directlink_flag);
1607
1608         rcu_read_lock();
1609         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1610                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
1611                         continue;
1612
1613                 if (hard_iface->soft_iface != if_incoming->soft_iface)
1614                         continue;
1615
1616                 if (batadv_compare_eth(ethhdr->h_source,
1617                                        hard_iface->net_dev->dev_addr))
1618                         is_my_addr = true;
1619
1620                 if (batadv_compare_eth(ogm_packet->orig,
1621                                        hard_iface->net_dev->dev_addr))
1622                         is_my_orig = true;
1623
1624                 if (batadv_compare_eth(ogm_packet->prev_sender,
1625                                        hard_iface->net_dev->dev_addr))
1626                         is_my_oldorig = true;
1627         }
1628         rcu_read_unlock();
1629
1630         if (is_my_addr) {
1631                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1632                            "Drop packet: received my own broadcast (sender: %pM)\n",
1633                            ethhdr->h_source);
1634                 return;
1635         }
1636
1637         if (is_my_orig) {
1638                 orig_neigh_node = batadv_iv_ogm_orig_get(bat_priv,
1639                                                          ethhdr->h_source);
1640                 if (!orig_neigh_node)
1641                         return;
1642
1643                 batadv_iv_ogm_process_reply(ogm_packet, if_incoming,
1644                                             orig_neigh_node, if_incoming_seqno);
1645
1646                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1647                            "Drop packet: originator packet from myself (via neighbor)\n");
1648                 batadv_orig_node_put(orig_neigh_node);
1649                 return;
1650         }
1651
1652         if (is_my_oldorig) {
1653                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1654                            "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1655                            ethhdr->h_source);
1656                 return;
1657         }
1658
1659         if (ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) {
1660                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1661                            "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1662                            ethhdr->h_source);
1663                 return;
1664         }
1665
1666         orig_node = batadv_iv_ogm_orig_get(bat_priv, ogm_packet->orig);
1667         if (!orig_node)
1668                 return;
1669
1670         batadv_iv_ogm_process_per_outif(skb, ogm_offset, orig_node,
1671                                         if_incoming, BATADV_IF_DEFAULT);
1672
1673         rcu_read_lock();
1674         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1675                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
1676                         continue;
1677
1678                 if (hard_iface->soft_iface != bat_priv->soft_iface)
1679                         continue;
1680
1681                 if (!kref_get_unless_zero(&hard_iface->refcount))
1682                         continue;
1683
1684                 batadv_iv_ogm_process_per_outif(skb, ogm_offset, orig_node,
1685                                                 if_incoming, hard_iface);
1686
1687                 batadv_hardif_put(hard_iface);
1688         }
1689         rcu_read_unlock();
1690
1691         batadv_orig_node_put(orig_node);
1692 }
1693
1694 static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work)
1695 {
1696         struct delayed_work *delayed_work;
1697         struct batadv_forw_packet *forw_packet;
1698         struct batadv_priv *bat_priv;
1699         bool dropped = false;
1700
1701         delayed_work = to_delayed_work(work);
1702         forw_packet = container_of(delayed_work, struct batadv_forw_packet,
1703                                    delayed_work);
1704         bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface);
1705
1706         if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) {
1707                 dropped = true;
1708                 goto out;
1709         }
1710
1711         batadv_iv_ogm_emit(forw_packet);
1712
1713         /* we have to have at least one packet in the queue to determine the
1714          * queues wake up time unless we are shutting down.
1715          *
1716          * only re-schedule if this is the "original" copy, e.g. the OGM of the
1717          * primary interface should only be rescheduled once per period, but
1718          * this function will be called for the forw_packet instances of the
1719          * other secondary interfaces as well.
1720          */
1721         if (forw_packet->own &&
1722             forw_packet->if_incoming == forw_packet->if_outgoing)
1723                 batadv_iv_ogm_schedule(forw_packet->if_incoming);
1724
1725 out:
1726         /* do we get something for free()? */
1727         if (batadv_forw_packet_steal(forw_packet,
1728                                      &bat_priv->forw_bat_list_lock))
1729                 batadv_forw_packet_free(forw_packet, dropped);
1730 }
1731
1732 static int batadv_iv_ogm_receive(struct sk_buff *skb,
1733                                  struct batadv_hard_iface *if_incoming)
1734 {
1735         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1736         struct batadv_ogm_packet *ogm_packet;
1737         u8 *packet_pos;
1738         int ogm_offset;
1739         bool res;
1740         int ret = NET_RX_DROP;
1741
1742         res = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
1743         if (!res)
1744                 goto free_skb;
1745
1746         /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1747          * that does not have B.A.T.M.A.N. IV enabled ?
1748          */
1749         if (bat_priv->algo_ops->iface.enable != batadv_iv_ogm_iface_enable)
1750                 goto free_skb;
1751
1752         batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
1753         batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
1754                            skb->len + ETH_HLEN);
1755
1756         ogm_offset = 0;
1757         ogm_packet = (struct batadv_ogm_packet *)skb->data;
1758
1759         /* unpack the aggregated packets and process them one by one */
1760         while (batadv_iv_ogm_aggr_packet(ogm_offset, skb_headlen(skb),
1761                                          ogm_packet)) {
1762                 batadv_iv_ogm_process(skb, ogm_offset, if_incoming);
1763
1764                 ogm_offset += BATADV_OGM_HLEN;
1765                 ogm_offset += ntohs(ogm_packet->tvlv_len);
1766
1767                 packet_pos = skb->data + ogm_offset;
1768                 ogm_packet = (struct batadv_ogm_packet *)packet_pos;
1769         }
1770
1771         ret = NET_RX_SUCCESS;
1772
1773 free_skb:
1774         if (ret == NET_RX_SUCCESS)
1775                 consume_skb(skb);
1776         else
1777                 kfree_skb(skb);
1778
1779         return ret;
1780 }
1781
1782 /**
1783  * batadv_iv_ogm_neigh_get_tq_avg() - Get the TQ average for a neighbour on a
1784  *  given outgoing interface.
1785  * @neigh_node: Neighbour of interest
1786  * @if_outgoing: Outgoing interface of interest
1787  * @tq_avg: Pointer of where to store the TQ average
1788  *
1789  * Return: False if no average TQ available, otherwise true.
1790  */
1791 static bool
1792 batadv_iv_ogm_neigh_get_tq_avg(struct batadv_neigh_node *neigh_node,
1793                                struct batadv_hard_iface *if_outgoing,
1794                                u8 *tq_avg)
1795 {
1796         struct batadv_neigh_ifinfo *n_ifinfo;
1797
1798         n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
1799         if (!n_ifinfo)
1800                 return false;
1801
1802         *tq_avg = n_ifinfo->bat_iv.tq_avg;
1803         batadv_neigh_ifinfo_put(n_ifinfo);
1804
1805         return true;
1806 }
1807
1808 /**
1809  * batadv_iv_ogm_orig_dump_subentry() - Dump an originator subentry into a
1810  *  message
1811  * @msg: Netlink message to dump into
1812  * @portid: Port making netlink request
1813  * @seq: Sequence number of netlink message
1814  * @bat_priv: The bat priv with all the soft interface information
1815  * @if_outgoing: Limit dump to entries with this outgoing interface
1816  * @orig_node: Originator to dump
1817  * @neigh_node: Single hops neighbour
1818  * @best: Is the best originator
1819  *
1820  * Return: Error code, or 0 on success
1821  */
1822 static int
1823 batadv_iv_ogm_orig_dump_subentry(struct sk_buff *msg, u32 portid, u32 seq,
1824                                  struct batadv_priv *bat_priv,
1825                                  struct batadv_hard_iface *if_outgoing,
1826                                  struct batadv_orig_node *orig_node,
1827                                  struct batadv_neigh_node *neigh_node,
1828                                  bool best)
1829 {
1830         void *hdr;
1831         u8 tq_avg;
1832         unsigned int last_seen_msecs;
1833
1834         last_seen_msecs = jiffies_to_msecs(jiffies - orig_node->last_seen);
1835
1836         if (!batadv_iv_ogm_neigh_get_tq_avg(neigh_node, if_outgoing, &tq_avg))
1837                 return 0;
1838
1839         if (if_outgoing != BATADV_IF_DEFAULT &&
1840             if_outgoing != neigh_node->if_incoming)
1841                 return 0;
1842
1843         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
1844                           NLM_F_MULTI, BATADV_CMD_GET_ORIGINATORS);
1845         if (!hdr)
1846                 return -ENOBUFS;
1847
1848         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
1849                     orig_node->orig) ||
1850             nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
1851                     neigh_node->addr) ||
1852             nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
1853                         neigh_node->if_incoming->net_dev->ifindex) ||
1854             nla_put_u8(msg, BATADV_ATTR_TQ, tq_avg) ||
1855             nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
1856                         last_seen_msecs))
1857                 goto nla_put_failure;
1858
1859         if (best && nla_put_flag(msg, BATADV_ATTR_FLAG_BEST))
1860                 goto nla_put_failure;
1861
1862         genlmsg_end(msg, hdr);
1863         return 0;
1864
1865  nla_put_failure:
1866         genlmsg_cancel(msg, hdr);
1867         return -EMSGSIZE;
1868 }
1869
1870 /**
1871  * batadv_iv_ogm_orig_dump_entry() - Dump an originator entry into a message
1872  * @msg: Netlink message to dump into
1873  * @portid: Port making netlink request
1874  * @seq: Sequence number of netlink message
1875  * @bat_priv: The bat priv with all the soft interface information
1876  * @if_outgoing: Limit dump to entries with this outgoing interface
1877  * @orig_node: Originator to dump
1878  * @sub_s: Number of sub entries to skip
1879  *
1880  * This function assumes the caller holds rcu_read_lock().
1881  *
1882  * Return: Error code, or 0 on success
1883  */
1884 static int
1885 batadv_iv_ogm_orig_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
1886                               struct batadv_priv *bat_priv,
1887                               struct batadv_hard_iface *if_outgoing,
1888                               struct batadv_orig_node *orig_node, int *sub_s)
1889 {
1890         struct batadv_neigh_node *neigh_node_best;
1891         struct batadv_neigh_node *neigh_node;
1892         int sub = 0;
1893         bool best;
1894         u8 tq_avg_best;
1895
1896         neigh_node_best = batadv_orig_router_get(orig_node, if_outgoing);
1897         if (!neigh_node_best)
1898                 goto out;
1899
1900         if (!batadv_iv_ogm_neigh_get_tq_avg(neigh_node_best, if_outgoing,
1901                                             &tq_avg_best))
1902                 goto out;
1903
1904         if (tq_avg_best == 0)
1905                 goto out;
1906
1907         hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
1908                 if (sub++ < *sub_s)
1909                         continue;
1910
1911                 best = (neigh_node == neigh_node_best);
1912
1913                 if (batadv_iv_ogm_orig_dump_subentry(msg, portid, seq,
1914                                                      bat_priv, if_outgoing,
1915                                                      orig_node, neigh_node,
1916                                                      best)) {
1917                         batadv_neigh_node_put(neigh_node_best);
1918
1919                         *sub_s = sub - 1;
1920                         return -EMSGSIZE;
1921                 }
1922         }
1923
1924  out:
1925         if (neigh_node_best)
1926                 batadv_neigh_node_put(neigh_node_best);
1927
1928         *sub_s = 0;
1929         return 0;
1930 }
1931
1932 /**
1933  * batadv_iv_ogm_orig_dump_bucket() - Dump an originator bucket into a
1934  *  message
1935  * @msg: Netlink message to dump into
1936  * @portid: Port making netlink request
1937  * @seq: Sequence number of netlink message
1938  * @bat_priv: The bat priv with all the soft interface information
1939  * @if_outgoing: Limit dump to entries with this outgoing interface
1940  * @head: Bucket to be dumped
1941  * @idx_s: Number of entries to be skipped
1942  * @sub: Number of sub entries to be skipped
1943  *
1944  * Return: Error code, or 0 on success
1945  */
1946 static int
1947 batadv_iv_ogm_orig_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
1948                                struct batadv_priv *bat_priv,
1949                                struct batadv_hard_iface *if_outgoing,
1950                                struct hlist_head *head, int *idx_s, int *sub)
1951 {
1952         struct batadv_orig_node *orig_node;
1953         int idx = 0;
1954
1955         rcu_read_lock();
1956         hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
1957                 if (idx++ < *idx_s)
1958                         continue;
1959
1960                 if (batadv_iv_ogm_orig_dump_entry(msg, portid, seq, bat_priv,
1961                                                   if_outgoing, orig_node,
1962                                                   sub)) {
1963                         rcu_read_unlock();
1964                         *idx_s = idx - 1;
1965                         return -EMSGSIZE;
1966                 }
1967         }
1968         rcu_read_unlock();
1969
1970         *idx_s = 0;
1971         *sub = 0;
1972         return 0;
1973 }
1974
1975 /**
1976  * batadv_iv_ogm_orig_dump() - Dump the originators into a message
1977  * @msg: Netlink message to dump into
1978  * @cb: Control block containing additional options
1979  * @bat_priv: The bat priv with all the soft interface information
1980  * @if_outgoing: Limit dump to entries with this outgoing interface
1981  */
1982 static void
1983 batadv_iv_ogm_orig_dump(struct sk_buff *msg, struct netlink_callback *cb,
1984                         struct batadv_priv *bat_priv,
1985                         struct batadv_hard_iface *if_outgoing)
1986 {
1987         struct batadv_hashtable *hash = bat_priv->orig_hash;
1988         struct hlist_head *head;
1989         int bucket = cb->args[0];
1990         int idx = cb->args[1];
1991         int sub = cb->args[2];
1992         int portid = NETLINK_CB(cb->skb).portid;
1993
1994         while (bucket < hash->size) {
1995                 head = &hash->table[bucket];
1996
1997                 if (batadv_iv_ogm_orig_dump_bucket(msg, portid,
1998                                                    cb->nlh->nlmsg_seq,
1999                                                    bat_priv, if_outgoing, head,
2000                                                    &idx, &sub))
2001                         break;
2002
2003                 bucket++;
2004         }
2005
2006         cb->args[0] = bucket;
2007         cb->args[1] = idx;
2008         cb->args[2] = sub;
2009 }
2010
2011 /**
2012  * batadv_iv_ogm_neigh_diff() - calculate tq difference of two neighbors
2013  * @neigh1: the first neighbor object of the comparison
2014  * @if_outgoing1: outgoing interface for the first neighbor
2015  * @neigh2: the second neighbor object of the comparison
2016  * @if_outgoing2: outgoing interface for the second neighbor
2017  * @diff: pointer to integer receiving the calculated difference
2018  *
2019  * The content of *@diff is only valid when this function returns true.
2020  * It is less, equal to or greater than 0 if the metric via neigh1 is lower,
2021  * the same as or higher than the metric via neigh2
2022  *
2023  * Return: true when the difference could be calculated, false otherwise
2024  */
2025 static bool batadv_iv_ogm_neigh_diff(struct batadv_neigh_node *neigh1,
2026                                      struct batadv_hard_iface *if_outgoing1,
2027                                      struct batadv_neigh_node *neigh2,
2028                                      struct batadv_hard_iface *if_outgoing2,
2029                                      int *diff)
2030 {
2031         struct batadv_neigh_ifinfo *neigh1_ifinfo, *neigh2_ifinfo;
2032         u8 tq1, tq2;
2033         bool ret = true;
2034
2035         neigh1_ifinfo = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
2036         neigh2_ifinfo = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
2037
2038         if (!neigh1_ifinfo || !neigh2_ifinfo) {
2039                 ret = false;
2040                 goto out;
2041         }
2042
2043         tq1 = neigh1_ifinfo->bat_iv.tq_avg;
2044         tq2 = neigh2_ifinfo->bat_iv.tq_avg;
2045         *diff = (int)tq1 - (int)tq2;
2046
2047 out:
2048         if (neigh1_ifinfo)
2049                 batadv_neigh_ifinfo_put(neigh1_ifinfo);
2050         if (neigh2_ifinfo)
2051                 batadv_neigh_ifinfo_put(neigh2_ifinfo);
2052
2053         return ret;
2054 }
2055
2056 /**
2057  * batadv_iv_ogm_neigh_dump_neigh() - Dump a neighbour into a netlink message
2058  * @msg: Netlink message to dump into
2059  * @portid: Port making netlink request
2060  * @seq: Sequence number of netlink message
2061  * @hardif_neigh: Neighbour to be dumped
2062  *
2063  * Return: Error code, or 0 on success
2064  */
2065 static int
2066 batadv_iv_ogm_neigh_dump_neigh(struct sk_buff *msg, u32 portid, u32 seq,
2067                                struct batadv_hardif_neigh_node *hardif_neigh)
2068 {
2069         void *hdr;
2070         unsigned int last_seen_msecs;
2071
2072         last_seen_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen);
2073
2074         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
2075                           NLM_F_MULTI, BATADV_CMD_GET_NEIGHBORS);
2076         if (!hdr)
2077                 return -ENOBUFS;
2078
2079         if (nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
2080                     hardif_neigh->addr) ||
2081             nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
2082                         hardif_neigh->if_incoming->net_dev->ifindex) ||
2083             nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
2084                         last_seen_msecs))
2085                 goto nla_put_failure;
2086
2087         genlmsg_end(msg, hdr);
2088         return 0;
2089
2090  nla_put_failure:
2091         genlmsg_cancel(msg, hdr);
2092         return -EMSGSIZE;
2093 }
2094
2095 /**
2096  * batadv_iv_ogm_neigh_dump_hardif() - Dump the neighbours of a hard interface
2097  *  into a message
2098  * @msg: Netlink message to dump into
2099  * @portid: Port making netlink request
2100  * @seq: Sequence number of netlink message
2101  * @bat_priv: The bat priv with all the soft interface information
2102  * @hard_iface: Hard interface to dump the neighbours for
2103  * @idx_s: Number of entries to skip
2104  *
2105  * This function assumes the caller holds rcu_read_lock().
2106  *
2107  * Return: Error code, or 0 on success
2108  */
2109 static int
2110 batadv_iv_ogm_neigh_dump_hardif(struct sk_buff *msg, u32 portid, u32 seq,
2111                                 struct batadv_priv *bat_priv,
2112                                 struct batadv_hard_iface *hard_iface,
2113                                 int *idx_s)
2114 {
2115         struct batadv_hardif_neigh_node *hardif_neigh;
2116         int idx = 0;
2117
2118         hlist_for_each_entry_rcu(hardif_neigh,
2119                                  &hard_iface->neigh_list, list) {
2120                 if (idx++ < *idx_s)
2121                         continue;
2122
2123                 if (batadv_iv_ogm_neigh_dump_neigh(msg, portid, seq,
2124                                                    hardif_neigh)) {
2125                         *idx_s = idx - 1;
2126                         return -EMSGSIZE;
2127                 }
2128         }
2129
2130         *idx_s = 0;
2131         return 0;
2132 }
2133
2134 /**
2135  * batadv_iv_ogm_neigh_dump() - Dump the neighbours into a message
2136  * @msg: Netlink message to dump into
2137  * @cb: Control block containing additional options
2138  * @bat_priv: The bat priv with all the soft interface information
2139  * @single_hardif: Limit dump to this hard interface
2140  */
2141 static void
2142 batadv_iv_ogm_neigh_dump(struct sk_buff *msg, struct netlink_callback *cb,
2143                          struct batadv_priv *bat_priv,
2144                          struct batadv_hard_iface *single_hardif)
2145 {
2146         struct batadv_hard_iface *hard_iface;
2147         int i_hardif = 0;
2148         int i_hardif_s = cb->args[0];
2149         int idx = cb->args[1];
2150         int portid = NETLINK_CB(cb->skb).portid;
2151
2152         rcu_read_lock();
2153         if (single_hardif) {
2154                 if (i_hardif_s == 0) {
2155                         if (batadv_iv_ogm_neigh_dump_hardif(msg, portid,
2156                                                             cb->nlh->nlmsg_seq,
2157                                                             bat_priv,
2158                                                             single_hardif,
2159                                                             &idx) == 0)
2160                                 i_hardif++;
2161                 }
2162         } else {
2163                 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list,
2164                                         list) {
2165                         if (hard_iface->soft_iface != bat_priv->soft_iface)
2166                                 continue;
2167
2168                         if (i_hardif++ < i_hardif_s)
2169                                 continue;
2170
2171                         if (batadv_iv_ogm_neigh_dump_hardif(msg, portid,
2172                                                             cb->nlh->nlmsg_seq,
2173                                                             bat_priv,
2174                                                             hard_iface, &idx)) {
2175                                 i_hardif--;
2176                                 break;
2177                         }
2178                 }
2179         }
2180         rcu_read_unlock();
2181
2182         cb->args[0] = i_hardif;
2183         cb->args[1] = idx;
2184 }
2185
2186 /**
2187  * batadv_iv_ogm_neigh_cmp() - compare the metrics of two neighbors
2188  * @neigh1: the first neighbor object of the comparison
2189  * @if_outgoing1: outgoing interface for the first neighbor
2190  * @neigh2: the second neighbor object of the comparison
2191  * @if_outgoing2: outgoing interface for the second neighbor
2192  *
2193  * Return: a value less, equal to or greater than 0 if the metric via neigh1 is
2194  * lower, the same as or higher than the metric via neigh2
2195  */
2196 static int batadv_iv_ogm_neigh_cmp(struct batadv_neigh_node *neigh1,
2197                                    struct batadv_hard_iface *if_outgoing1,
2198                                    struct batadv_neigh_node *neigh2,
2199                                    struct batadv_hard_iface *if_outgoing2)
2200 {
2201         bool ret;
2202         int diff;
2203
2204         ret = batadv_iv_ogm_neigh_diff(neigh1, if_outgoing1, neigh2,
2205                                        if_outgoing2, &diff);
2206         if (!ret)
2207                 return 0;
2208
2209         return diff;
2210 }
2211
2212 /**
2213  * batadv_iv_ogm_neigh_is_sob() - check if neigh1 is similarly good or better
2214  *  than neigh2 from the metric prospective
2215  * @neigh1: the first neighbor object of the comparison
2216  * @if_outgoing1: outgoing interface for the first neighbor
2217  * @neigh2: the second neighbor object of the comparison
2218  * @if_outgoing2: outgoing interface for the second neighbor
2219  *
2220  * Return: true if the metric via neigh1 is equally good or better than
2221  * the metric via neigh2, false otherwise.
2222  */
2223 static bool
2224 batadv_iv_ogm_neigh_is_sob(struct batadv_neigh_node *neigh1,
2225                            struct batadv_hard_iface *if_outgoing1,
2226                            struct batadv_neigh_node *neigh2,
2227                            struct batadv_hard_iface *if_outgoing2)
2228 {
2229         bool ret;
2230         int diff;
2231
2232         ret = batadv_iv_ogm_neigh_diff(neigh1, if_outgoing1, neigh2,
2233                                        if_outgoing2, &diff);
2234         if (!ret)
2235                 return false;
2236
2237         ret = diff > -BATADV_TQ_SIMILARITY_THRESHOLD;
2238         return ret;
2239 }
2240
2241 static void batadv_iv_iface_enabled(struct batadv_hard_iface *hard_iface)
2242 {
2243         /* begin scheduling originator messages on that interface */
2244         batadv_iv_ogm_schedule(hard_iface);
2245 }
2246
2247 /**
2248  * batadv_iv_init_sel_class() - initialize GW selection class
2249  * @bat_priv: the bat priv with all the soft interface information
2250  */
2251 static void batadv_iv_init_sel_class(struct batadv_priv *bat_priv)
2252 {
2253         /* set default TQ difference threshold to 20 */
2254         atomic_set(&bat_priv->gw.sel_class, 20);
2255 }
2256
2257 static struct batadv_gw_node *
2258 batadv_iv_gw_get_best_gw_node(struct batadv_priv *bat_priv)
2259 {
2260         struct batadv_neigh_node *router;
2261         struct batadv_neigh_ifinfo *router_ifinfo;
2262         struct batadv_gw_node *gw_node, *curr_gw = NULL;
2263         u64 max_gw_factor = 0;
2264         u64 tmp_gw_factor = 0;
2265         u8 max_tq = 0;
2266         u8 tq_avg;
2267         struct batadv_orig_node *orig_node;
2268
2269         rcu_read_lock();
2270         hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
2271                 orig_node = gw_node->orig_node;
2272                 router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
2273                 if (!router)
2274                         continue;
2275
2276                 router_ifinfo = batadv_neigh_ifinfo_get(router,
2277                                                         BATADV_IF_DEFAULT);
2278                 if (!router_ifinfo)
2279                         goto next;
2280
2281                 if (!kref_get_unless_zero(&gw_node->refcount))
2282                         goto next;
2283
2284                 tq_avg = router_ifinfo->bat_iv.tq_avg;
2285
2286                 switch (atomic_read(&bat_priv->gw.sel_class)) {
2287                 case 1: /* fast connection */
2288                         tmp_gw_factor = tq_avg * tq_avg;
2289                         tmp_gw_factor *= gw_node->bandwidth_down;
2290                         tmp_gw_factor *= 100 * 100;
2291                         tmp_gw_factor >>= 18;
2292
2293                         if (tmp_gw_factor > max_gw_factor ||
2294                             (tmp_gw_factor == max_gw_factor &&
2295                              tq_avg > max_tq)) {
2296                                 if (curr_gw)
2297                                         batadv_gw_node_put(curr_gw);
2298                                 curr_gw = gw_node;
2299                                 kref_get(&curr_gw->refcount);
2300                         }
2301                         break;
2302
2303                 default: /* 2:  stable connection (use best statistic)
2304                           * 3:  fast-switch (use best statistic but change as
2305                           *     soon as a better gateway appears)
2306                           * XX: late-switch (use best statistic but change as
2307                           *     soon as a better gateway appears which has
2308                           *     $routing_class more tq points)
2309                           */
2310                         if (tq_avg > max_tq) {
2311                                 if (curr_gw)
2312                                         batadv_gw_node_put(curr_gw);
2313                                 curr_gw = gw_node;
2314                                 kref_get(&curr_gw->refcount);
2315                         }
2316                         break;
2317                 }
2318
2319                 if (tq_avg > max_tq)
2320                         max_tq = tq_avg;
2321
2322                 if (tmp_gw_factor > max_gw_factor)
2323                         max_gw_factor = tmp_gw_factor;
2324
2325                 batadv_gw_node_put(gw_node);
2326
2327 next:
2328                 batadv_neigh_node_put(router);
2329                 if (router_ifinfo)
2330                         batadv_neigh_ifinfo_put(router_ifinfo);
2331         }
2332         rcu_read_unlock();
2333
2334         return curr_gw;
2335 }
2336
2337 static bool batadv_iv_gw_is_eligible(struct batadv_priv *bat_priv,
2338                                      struct batadv_orig_node *curr_gw_orig,
2339                                      struct batadv_orig_node *orig_node)
2340 {
2341         struct batadv_neigh_ifinfo *router_orig_ifinfo = NULL;
2342         struct batadv_neigh_ifinfo *router_gw_ifinfo = NULL;
2343         struct batadv_neigh_node *router_gw = NULL;
2344         struct batadv_neigh_node *router_orig = NULL;
2345         u8 gw_tq_avg, orig_tq_avg;
2346         bool ret = false;
2347
2348         /* dynamic re-election is performed only on fast or late switch */
2349         if (atomic_read(&bat_priv->gw.sel_class) <= 2)
2350                 return false;
2351
2352         router_gw = batadv_orig_router_get(curr_gw_orig, BATADV_IF_DEFAULT);
2353         if (!router_gw) {
2354                 ret = true;
2355                 goto out;
2356         }
2357
2358         router_gw_ifinfo = batadv_neigh_ifinfo_get(router_gw,
2359                                                    BATADV_IF_DEFAULT);
2360         if (!router_gw_ifinfo) {
2361                 ret = true;
2362                 goto out;
2363         }
2364
2365         router_orig = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
2366         if (!router_orig)
2367                 goto out;
2368
2369         router_orig_ifinfo = batadv_neigh_ifinfo_get(router_orig,
2370                                                      BATADV_IF_DEFAULT);
2371         if (!router_orig_ifinfo)
2372                 goto out;
2373
2374         gw_tq_avg = router_gw_ifinfo->bat_iv.tq_avg;
2375         orig_tq_avg = router_orig_ifinfo->bat_iv.tq_avg;
2376
2377         /* the TQ value has to be better */
2378         if (orig_tq_avg < gw_tq_avg)
2379                 goto out;
2380
2381         /* if the routing class is greater than 3 the value tells us how much
2382          * greater the TQ value of the new gateway must be
2383          */
2384         if ((atomic_read(&bat_priv->gw.sel_class) > 3) &&
2385             (orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw.sel_class)))
2386                 goto out;
2387
2388         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
2389                    "Restarting gateway selection: better gateway found (tq curr: %i, tq new: %i)\n",
2390                    gw_tq_avg, orig_tq_avg);
2391
2392         ret = true;
2393 out:
2394         if (router_gw_ifinfo)
2395                 batadv_neigh_ifinfo_put(router_gw_ifinfo);
2396         if (router_orig_ifinfo)
2397                 batadv_neigh_ifinfo_put(router_orig_ifinfo);
2398         if (router_gw)
2399                 batadv_neigh_node_put(router_gw);
2400         if (router_orig)
2401                 batadv_neigh_node_put(router_orig);
2402
2403         return ret;
2404 }
2405
2406 /**
2407  * batadv_iv_gw_dump_entry() - Dump a gateway into a message
2408  * @msg: Netlink message to dump into
2409  * @portid: Port making netlink request
2410  * @cb: Control block containing additional options
2411  * @bat_priv: The bat priv with all the soft interface information
2412  * @gw_node: Gateway to be dumped
2413  *
2414  * Return: Error code, or 0 on success
2415  */
2416 static int batadv_iv_gw_dump_entry(struct sk_buff *msg, u32 portid,
2417                                    struct netlink_callback *cb,
2418                                    struct batadv_priv *bat_priv,
2419                                    struct batadv_gw_node *gw_node)
2420 {
2421         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
2422         struct batadv_neigh_node *router;
2423         struct batadv_gw_node *curr_gw = NULL;
2424         int ret = 0;
2425         void *hdr;
2426
2427         router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
2428         if (!router)
2429                 goto out;
2430
2431         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
2432         if (!router_ifinfo)
2433                 goto out;
2434
2435         curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
2436
2437         hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
2438                           &batadv_netlink_family, NLM_F_MULTI,
2439                           BATADV_CMD_GET_GATEWAYS);
2440         if (!hdr) {
2441                 ret = -ENOBUFS;
2442                 goto out;
2443         }
2444
2445         genl_dump_check_consistent(cb, hdr);
2446
2447         ret = -EMSGSIZE;
2448
2449         if (curr_gw == gw_node)
2450                 if (nla_put_flag(msg, BATADV_ATTR_FLAG_BEST)) {
2451                         genlmsg_cancel(msg, hdr);
2452                         goto out;
2453                 }
2454
2455         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
2456                     gw_node->orig_node->orig) ||
2457             nla_put_u8(msg, BATADV_ATTR_TQ, router_ifinfo->bat_iv.tq_avg) ||
2458             nla_put(msg, BATADV_ATTR_ROUTER, ETH_ALEN,
2459                     router->addr) ||
2460             nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
2461                            router->if_incoming->net_dev->name) ||
2462             nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_DOWN,
2463                         gw_node->bandwidth_down) ||
2464             nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_UP,
2465                         gw_node->bandwidth_up)) {
2466                 genlmsg_cancel(msg, hdr);
2467                 goto out;
2468         }
2469
2470         genlmsg_end(msg, hdr);
2471         ret = 0;
2472
2473 out:
2474         if (curr_gw)
2475                 batadv_gw_node_put(curr_gw);
2476         if (router_ifinfo)
2477                 batadv_neigh_ifinfo_put(router_ifinfo);
2478         if (router)
2479                 batadv_neigh_node_put(router);
2480         return ret;
2481 }
2482
2483 /**
2484  * batadv_iv_gw_dump() - Dump gateways into a message
2485  * @msg: Netlink message to dump into
2486  * @cb: Control block containing additional options
2487  * @bat_priv: The bat priv with all the soft interface information
2488  */
2489 static void batadv_iv_gw_dump(struct sk_buff *msg, struct netlink_callback *cb,
2490                               struct batadv_priv *bat_priv)
2491 {
2492         int portid = NETLINK_CB(cb->skb).portid;
2493         struct batadv_gw_node *gw_node;
2494         int idx_skip = cb->args[0];
2495         int idx = 0;
2496
2497         spin_lock_bh(&bat_priv->gw.list_lock);
2498         cb->seq = bat_priv->gw.generation << 1 | 1;
2499
2500         hlist_for_each_entry(gw_node, &bat_priv->gw.gateway_list, list) {
2501                 if (idx++ < idx_skip)
2502                         continue;
2503
2504                 if (batadv_iv_gw_dump_entry(msg, portid, cb, bat_priv,
2505                                             gw_node)) {
2506                         idx_skip = idx - 1;
2507                         goto unlock;
2508                 }
2509         }
2510
2511         idx_skip = idx;
2512 unlock:
2513         spin_unlock_bh(&bat_priv->gw.list_lock);
2514
2515         cb->args[0] = idx_skip;
2516 }
2517
2518 static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
2519         .name = "BATMAN_IV",
2520         .iface = {
2521                 .enable = batadv_iv_ogm_iface_enable,
2522                 .enabled = batadv_iv_iface_enabled,
2523                 .disable = batadv_iv_ogm_iface_disable,
2524                 .update_mac = batadv_iv_ogm_iface_update_mac,
2525                 .primary_set = batadv_iv_ogm_primary_iface_set,
2526         },
2527         .neigh = {
2528                 .cmp = batadv_iv_ogm_neigh_cmp,
2529                 .is_similar_or_better = batadv_iv_ogm_neigh_is_sob,
2530                 .dump = batadv_iv_ogm_neigh_dump,
2531         },
2532         .orig = {
2533                 .dump = batadv_iv_ogm_orig_dump,
2534         },
2535         .gw = {
2536                 .init_sel_class = batadv_iv_init_sel_class,
2537                 .get_best_gw_node = batadv_iv_gw_get_best_gw_node,
2538                 .is_eligible = batadv_iv_gw_is_eligible,
2539                 .dump = batadv_iv_gw_dump,
2540         },
2541 };
2542
2543 /**
2544  * batadv_iv_init() - B.A.T.M.A.N. IV initialization function
2545  *
2546  * Return: 0 on success or negative error number in case of failure
2547  */
2548 int __init batadv_iv_init(void)
2549 {
2550         int ret;
2551
2552         /* batman originator packet */
2553         ret = batadv_recv_handler_register(BATADV_IV_OGM,
2554                                            batadv_iv_ogm_receive);
2555         if (ret < 0)
2556                 goto out;
2557
2558         ret = batadv_algo_register(&batadv_batman_iv);
2559         if (ret < 0)
2560                 goto handler_unregister;
2561
2562         goto out;
2563
2564 handler_unregister:
2565         batadv_recv_handler_unregister(BATADV_IV_OGM);
2566 out:
2567         return ret;
2568 }