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 (forw_packet->if_outgoing->soft_iface != soft_iface) {
 413                 pr_warn("%s: soft interface switch for queued OGM\n", __func__);
 414                 return;
 415         }
 416
 417         if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE)
 418                 return;
 419
 420         /* only for one specific outgoing interface */
 421         batadv_iv_ogm_send_to_if(forw_packet, forw_packet->if_outgoing);
 422 }
 423
 424 /**
 425  * batadv_iv_ogm_can_aggregate() - find out if an OGM can be aggregated on an
 426  *  existing forward packet
 427  * @new_bat_ogm_packet: OGM packet to be aggregated
 428  * @bat_priv: the bat priv with all the soft interface information
 429  * @packet_len: (total) length of the OGM
 430  * @send_time: timestamp (jiffies) when the packet is to be sent
 431  * @directlink: true if this is a direct link packet
 432  * @if_incoming: interface where the packet was received
 433  * @if_outgoing: interface for which the retransmission should be considered
 434  * @forw_packet: the forwarded packet which should be checked
 435  *
 436  * Return: true if new_packet can be aggregated with forw_packet
 437  */
 438 static bool
 439 batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet,
 440                             struct batadv_priv *bat_priv,
 441                             int packet_len, unsigned long send_time,
 442                             bool directlink,
 443                             const struct batadv_hard_iface *if_incoming,
 444                             const struct batadv_hard_iface *if_outgoing,
 445                             const struct batadv_forw_packet *forw_packet)
 446 {
 447         struct batadv_ogm_packet *batadv_ogm_packet;
 448         int aggregated_bytes = forw_packet->packet_len + packet_len;
 449         struct batadv_hard_iface *primary_if = NULL;
 450         bool res = false;
 451         unsigned long aggregation_end_time;
 452
 453         batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
 454         aggregation_end_time = send_time;
 455         aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 456
 457         /* we can aggregate the current packet to this aggregated packet
 458          * if:
 459          *
 460          * - the send time is within our MAX_AGGREGATION_MS time
 461          * - the resulting packet won't be bigger than
 462          *   MAX_AGGREGATION_BYTES
 463          * otherwise aggregation is not possible
 464          */
 465         if (!time_before(send_time, forw_packet->send_time) ||
 466             !time_after_eq(aggregation_end_time, forw_packet->send_time))
 467                 return false;
 468
 469         if (aggregated_bytes > BATADV_MAX_AGGREGATION_BYTES)
 470                 return false;
 471
 472         /* packet is not leaving on the same interface. */
 473         if (forw_packet->if_outgoing != if_outgoing)
 474                 return false;
 475
 476         /* check aggregation compatibility
 477          * -> direct link packets are broadcasted on
 478          *    their interface only
 479          * -> aggregate packet if the current packet is
 480          *    a "global" packet as well as the base
 481          *    packet
 482          */
 483         primary_if = batadv_primary_if_get_selected(bat_priv);
 484         if (!primary_if)
 485                 return false;
 486
 487         /* packets without direct link flag and high TTL
 488          * are flooded through the net
 489          */
 490         if (!directlink &&
 491             !(batadv_ogm_packet->flags & BATADV_DIRECTLINK) &&
 492             batadv_ogm_packet->ttl != 1 &&
 493
 494             /* own packets originating non-primary
 495              * interfaces leave only that interface
 496              */
 497             (!forw_packet->own ||
 498              forw_packet->if_incoming == primary_if)) {
 499                 res = true;
 500                 goto out;
 501         }
 502
 503         /* if the incoming packet is sent via this one
 504          * interface only - we still can aggregate
 505          */
 506         if (directlink &&
 507             new_bat_ogm_packet->ttl == 1 &&
 508             forw_packet->if_incoming == if_incoming &&
 509
 510             /* packets from direct neighbors or
 511              * own secondary interface packets
 512              * (= secondary interface packets in general)
 513              */
 514             (batadv_ogm_packet->flags & BATADV_DIRECTLINK ||
 515              (forw_packet->own &&
 516               forw_packet->if_incoming != primary_if))) {
 517                 res = true;
 518                 goto out;
 519         }
 520
 521 out:
 522         batadv_hardif_put(primary_if);
 523         return res;
 524 }
 525
 526 /**
 527  * batadv_iv_ogm_aggregate_new() - create a new aggregated packet and add this
 528  *  packet to it.
 529  * @packet_buff: pointer to the OGM
 530  * @packet_len: (total) length of the OGM
 531  * @send_time: timestamp (jiffies) when the packet is to be sent
 532  * @direct_link: whether this OGM has direct link status
 533  * @if_incoming: interface where the packet was received
 534  * @if_outgoing: interface for which the retransmission should be considered
 535  * @own_packet: true if it is a self-generated ogm
 536  */
 537 static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 538                                         int packet_len, unsigned long send_time,
 539                                         bool direct_link,
 540                                         struct batadv_hard_iface *if_incoming,
 541                                         struct batadv_hard_iface *if_outgoing,
 542                                         int own_packet)
 543 {
 544         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 545         struct batadv_forw_packet *forw_packet_aggr;
 546         struct sk_buff *skb;
 547         unsigned char *skb_buff;
 548         unsigned int skb_size;
 549         atomic_t *queue_left = own_packet ? NULL : &bat_priv->batman_queue_left;
 550
 551         if (atomic_read(&bat_priv->aggregated_ogms) &&
 552             packet_len < BATADV_MAX_AGGREGATION_BYTES)
 553                 skb_size = BATADV_MAX_AGGREGATION_BYTES;
 554         else
 555                 skb_size = packet_len;
 556
 557         skb_size += ETH_HLEN;
 558
 559         skb = netdev_alloc_skb_ip_align(NULL, skb_size);
 560         if (!skb)
 561                 return;
 562
 563         forw_packet_aggr = batadv_forw_packet_alloc(if_incoming, if_outgoing,
 564                                                     queue_left, bat_priv, skb);
 565         if (!forw_packet_aggr) {
 566                 kfree_skb(skb);
 567                 return;
 568         }
 569
 570         forw_packet_aggr->skb->priority = TC_PRIO_CONTROL;
 571         skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
 572
 573         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 574         forw_packet_aggr->packet_len = packet_len;
 575         memcpy(skb_buff, packet_buff, packet_len);
 576
 577         forw_packet_aggr->own = own_packet;
 578         forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
 579         forw_packet_aggr->send_time = send_time;
 580
 581         /* save packet direct link flag status */
 582         if (direct_link)
 583                 forw_packet_aggr->direct_link_flags |= 1;
 584
 585         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 586                           batadv_iv_send_outstanding_bat_ogm_packet);
 587
 588         batadv_forw_packet_ogmv1_queue(bat_priv, forw_packet_aggr, send_time);
 589 }
 590
 591 /* aggregate a new packet into the existing ogm packet */
 592 static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr,
 593                                     const unsigned char *packet_buff,
 594                                     int packet_len, bool direct_link)
 595 {
 596         unsigned long new_direct_link_flag;
 597
 598         skb_put_data(forw_packet_aggr->skb, packet_buff, packet_len);
 599         forw_packet_aggr->packet_len += packet_len;
 600         forw_packet_aggr->num_packets++;
 601
 602         /* save packet direct link flag status */
 603         if (direct_link) {
 604                 new_direct_link_flag = BIT(forw_packet_aggr->num_packets);
 605                 forw_packet_aggr->direct_link_flags |= new_direct_link_flag;
 606         }
 607 }
 608
 609 /**
 610  * batadv_iv_ogm_queue_add() - queue up an OGM for transmission
 611  * @bat_priv: the bat priv with all the soft interface information
 612  * @packet_buff: pointer to the OGM
 613  * @packet_len: (total) length of the OGM
 614  * @if_incoming: interface where the packet was received
 615  * @if_outgoing: interface for which the retransmission should be considered
 616  * @own_packet: true if it is a self-generated ogm
 617  * @send_time: timestamp (jiffies) when the packet is to be sent
 618  */
 619 static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv,
 620                                     unsigned char *packet_buff,
 621                                     int packet_len,
 622                                     struct batadv_hard_iface *if_incoming,
 623                                     struct batadv_hard_iface *if_outgoing,
 624                                     int own_packet, unsigned long send_time)
 625 {
 626         /* _aggr -> pointer to the packet we want to aggregate with
 627          * _pos -> pointer to the position in the queue
 628          */
 629         struct batadv_forw_packet *forw_packet_aggr = NULL;
 630         struct batadv_forw_packet *forw_packet_pos = NULL;
 631         struct batadv_ogm_packet *batadv_ogm_packet;
 632         bool direct_link;
 633         unsigned long max_aggregation_jiffies;
 634
 635         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
 636         direct_link = !!(batadv_ogm_packet->flags & BATADV_DIRECTLINK);
 637         max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 638
 639         /* find position for the packet in the forward queue */
 640         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 641         /* own packets are not to be aggregated */
 642         if (atomic_read(&bat_priv->aggregated_ogms) && !own_packet) {
 643                 hlist_for_each_entry(forw_packet_pos,
 644                                      &bat_priv->forw_bat_list, list) {
 645                         if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet,
 646                                                         bat_priv, packet_len,
 647                                                         send_time, direct_link,
 648                                                         if_incoming,
 649                                                         if_outgoing,
 650                                                         forw_packet_pos)) {
 651                                 forw_packet_aggr = forw_packet_pos;
 652                                 break;
 653                         }
 654                 }
 655         }
 656
 657         /* nothing to aggregate with - either aggregation disabled or no
 658          * suitable aggregation packet found
 659          */
 660         if (!forw_packet_aggr) {
 661                 /* the following section can run without the lock */
 662                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 663
 664                 /* if we could not aggregate this packet with one of the others
 665                  * we hold it back for a while, so that it might be aggregated
 666                  * later on
 667                  */
 668                 if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
 669                         send_time += max_aggregation_jiffies;
 670
 671                 batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
 672                                             send_time, direct_link,
 673                                             if_incoming, if_outgoing,
 674                                             own_packet);
 675         } else {
 676                 batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 677                                         packet_len, direct_link);
 678                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 679         }
 680 }
 681
 682 static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
 683                                   const struct ethhdr *ethhdr,
 684                                   struct batadv_ogm_packet *batadv_ogm_packet,
 685                                   bool is_single_hop_neigh,
 686                                   bool is_from_best_next_hop,
 687                                   struct batadv_hard_iface *if_incoming,
 688                                   struct batadv_hard_iface *if_outgoing)
 689 {
 690         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 691         u16 tvlv_len;
 692
 693         if (batadv_ogm_packet->ttl <= 1) {
 694                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
 695                 return;
 696         }
 697
 698         if (!is_from_best_next_hop) {
 699                 /* Mark the forwarded packet when it is not coming from our
 700                  * best next hop. We still need to forward the packet for our
 701                  * neighbor link quality detection to work in case the packet
 702                  * originated from a single hop neighbor. Otherwise we can
 703                  * simply drop the ogm.
 704                  */
 705                 if (is_single_hop_neigh)
 706                         batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP;
 707                 else
 708                         return;
 709         }
 710
 711         tvlv_len = ntohs(batadv_ogm_packet->tvlv_len);
 712
 713         batadv_ogm_packet->ttl--;
 714         ether_addr_copy(batadv_ogm_packet->prev_sender, ethhdr->h_source);
 715
 716         /* apply hop penalty */
 717         batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq,
 718                                                    bat_priv);
 719
 720         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 721                    "Forwarding packet: tq: %i, ttl: %i\n",
 722                    batadv_ogm_packet->tq, batadv_ogm_packet->ttl);
 723
 724         if (is_single_hop_neigh)
 725                 batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 726         else
 727                 batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 728
 729         batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
 730                                 BATADV_OGM_HLEN + tvlv_len,
 731                                 if_incoming, if_outgoing, 0,
 732                                 batadv_iv_ogm_fwd_send_time());
 733 }
 734
 735 /**
 736  * batadv_iv_ogm_slide_own_bcast_window() - bitshift own OGM broadcast windows
 737  *  for the given interface
 738  * @hard_iface: the interface for which the windows have to be shifted
 739  */
 740 static void
 741 batadv_iv_ogm_slide_own_bcast_window(struct batadv_hard_iface *hard_iface)
 742 {
 743         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 744         struct batadv_hashtable *hash = bat_priv->orig_hash;
 745         struct hlist_head *head;
 746         struct batadv_orig_node *orig_node;
 747         struct batadv_orig_ifinfo *orig_ifinfo;
 748         unsigned long *word;
 749         u32 i;
 750         u8 *w;
 751
 752         for (i = 0; i < hash->size; i++) {
 753                 head = &hash->table[i];
 754
 755                 rcu_read_lock();
 756                 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
 757                         hlist_for_each_entry_rcu(orig_ifinfo,
 758                                                  &orig_node->ifinfo_list,
 759                                                  list) {
 760                                 if (orig_ifinfo->if_outgoing != hard_iface)
 761                                         continue;
 762
 763                                 spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 764                                 word = orig_ifinfo->bat_iv.bcast_own;
 765                                 batadv_bit_get_packet(bat_priv, word, 1, 0);
 766                                 w = &orig_ifinfo->bat_iv.bcast_own_sum;
 767                                 *w = bitmap_weight(word,
 768                                                    BATADV_TQ_LOCAL_WINDOW_SIZE);
 769                                 spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 770                         }
 771                 }
 772                 rcu_read_unlock();
 773         }
 774 }
 775
 776 /**
 777  * batadv_iv_ogm_schedule_buff() - schedule submission of hardif ogm buffer
 778  * @hard_iface: interface whose ogm buffer should be transmitted
 779  */
 780 static void batadv_iv_ogm_schedule_buff(struct batadv_hard_iface *hard_iface)
 781 {
 782         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 783         unsigned char **ogm_buff = &hard_iface->bat_iv.ogm_buff;
 784         struct batadv_ogm_packet *batadv_ogm_packet;
 785         struct batadv_hard_iface *primary_if, *tmp_hard_iface;
 786         int *ogm_buff_len = &hard_iface->bat_iv.ogm_buff_len;
 787         u32 seqno;
 788         u16 tvlv_len = 0;
 789         unsigned long send_time;
 790
 791         lockdep_assert_held(&hard_iface->bat_iv.ogm_buff_mutex);
 792
 793         /* interface already disabled by batadv_iv_ogm_iface_disable */
 794         if (!*ogm_buff)
 795                 return;
 796
 797         /* the interface gets activated here to avoid race conditions between
 798          * the moment of activating the interface in
 799          * hardif_activate_interface() where the originator mac is set and
 800          * outdated packets (especially uninitialized mac addresses) in the
 801          * packet queue
 802          */
 803         if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED)
 804                 hard_iface->if_status = BATADV_IF_ACTIVE;
 805
 806         primary_if = batadv_primary_if_get_selected(bat_priv);
 807
 808         if (hard_iface == primary_if) {
 809                 /* tt changes have to be committed before the tvlv data is
 810                  * appended as it may alter the tt tvlv container
 811                  */
 812                 batadv_tt_local_commit_changes(bat_priv);
 813                 tvlv_len = batadv_tvlv_container_ogm_append(bat_priv, ogm_buff,
 814                                                             ogm_buff_len,
 815                                                             BATADV_OGM_HLEN);
 816         }
 817
 818         batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff);
 819         batadv_ogm_packet->tvlv_len = htons(tvlv_len);
 820
 821         /* change sequence number to network order */
 822         seqno = (u32)atomic_read(&hard_iface->bat_iv.ogm_seqno);
 823         batadv_ogm_packet->seqno = htonl(seqno);
 824         atomic_inc(&hard_iface->bat_iv.ogm_seqno);
 825
 826         batadv_iv_ogm_slide_own_bcast_window(hard_iface);
 827
 828         send_time = batadv_iv_ogm_emit_send_time(bat_priv);
 829
 830         if (hard_iface != primary_if) {
 831                 /* OGMs from secondary interfaces are only scheduled on their
 832                  * respective interfaces.
 833                  */
 834                 batadv_iv_ogm_queue_add(bat_priv, *ogm_buff, *ogm_buff_len,
 835                                         hard_iface, hard_iface, 1, send_time);
 836                 goto out;
 837         }
 838
 839         /* OGMs from primary interfaces are scheduled on all
 840          * interfaces.
 841          */
 842         rcu_read_lock();
 843         list_for_each_entry_rcu(tmp_hard_iface, &batadv_hardif_list, list) {
 844                 if (tmp_hard_iface->soft_iface != hard_iface->soft_iface)
 845                         continue;
 846
 847                 if (!kref_get_unless_zero(&tmp_hard_iface->refcount))
 848                         continue;
 849
 850                 batadv_iv_ogm_queue_add(bat_priv, *ogm_buff,
 851                                         *ogm_buff_len, hard_iface,
 852                                         tmp_hard_iface, 1, send_time);
 853
 854                 batadv_hardif_put(tmp_hard_iface);
 855         }
 856         rcu_read_unlock();
 857
 858 out:
 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         batadv_neigh_node_put(neigh_node);
1048         batadv_neigh_node_put(router);
1049         batadv_neigh_ifinfo_put(neigh_ifinfo);
1050         batadv_neigh_ifinfo_put(router_ifinfo);
1051 }
1052
1053 /**
1054  * batadv_iv_ogm_calc_tq() - calculate tq for current received ogm packet
1055  * @orig_node: the orig node who originally emitted the ogm packet
1056  * @orig_neigh_node: the orig node struct of the neighbor who sent the packet
1057  * @batadv_ogm_packet: the ogm packet
1058  * @if_incoming: interface where the packet was received
1059  * @if_outgoing: interface for which the retransmission should be considered
1060  *
1061  * Return: true if the link can be considered bidirectional, false otherwise
1062  */
1063 static bool batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
1064                                   struct batadv_orig_node *orig_neigh_node,
1065                                   struct batadv_ogm_packet *batadv_ogm_packet,
1066                                   struct batadv_hard_iface *if_incoming,
1067                                   struct batadv_hard_iface *if_outgoing)
1068 {
1069         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1070         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node;
1071         struct batadv_neigh_ifinfo *neigh_ifinfo;
1072         u8 total_count;
1073         u8 orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
1074         unsigned int tq_iface_hop_penalty = BATADV_TQ_MAX_VALUE;
1075         unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
1076         unsigned int tq_asym_penalty, inv_asym_penalty;
1077         unsigned int combined_tq;
1078         bool ret = false;
1079
1080         /* find corresponding one hop neighbor */
1081         rcu_read_lock();
1082         hlist_for_each_entry_rcu(tmp_neigh_node,
1083                                  &orig_neigh_node->neigh_list, list) {
1084                 if (!batadv_compare_eth(tmp_neigh_node->addr,
1085                                         orig_neigh_node->orig))
1086                         continue;
1087
1088                 if (tmp_neigh_node->if_incoming != if_incoming)
1089                         continue;
1090
1091                 if (!kref_get_unless_zero(&tmp_neigh_node->refcount))
1092                         continue;
1093
1094                 neigh_node = tmp_neigh_node;
1095                 break;
1096         }
1097         rcu_read_unlock();
1098
1099         if (!neigh_node)
1100                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
1101                                                      orig_neigh_node->orig,
1102                                                      orig_neigh_node,
1103                                                      orig_neigh_node);
1104
1105         if (!neigh_node)
1106                 goto out;
1107
1108         /* if orig_node is direct neighbor update neigh_node last_seen */
1109         if (orig_node == orig_neigh_node)
1110                 neigh_node->last_seen = jiffies;
1111
1112         orig_node->last_seen = jiffies;
1113
1114         /* find packet count of corresponding one hop neighbor */
1115         orig_eq_count = batadv_iv_orig_ifinfo_sum(orig_neigh_node, if_incoming);
1116         neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing);
1117         if (neigh_ifinfo) {
1118                 neigh_rq_count = neigh_ifinfo->bat_iv.real_packet_count;
1119                 batadv_neigh_ifinfo_put(neigh_ifinfo);
1120         } else {
1121                 neigh_rq_count = 0;
1122         }
1123
1124         /* pay attention to not get a value bigger than 100 % */
1125         if (orig_eq_count > neigh_rq_count)
1126                 total_count = neigh_rq_count;
1127         else
1128                 total_count = orig_eq_count;
1129
1130         /* if we have too few packets (too less data) we set tq_own to zero
1131          * if we receive too few packets it is not considered bidirectional
1132          */
1133         if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
1134             neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
1135                 tq_own = 0;
1136         else
1137                 /* neigh_node->real_packet_count is never zero as we
1138                  * only purge old information when getting new
1139                  * information
1140                  */
1141                 tq_own = (BATADV_TQ_MAX_VALUE * total_count) /  neigh_rq_count;
1142
1143         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
1144          * affect the nearly-symmetric links only a little, but
1145          * punishes asymmetric links more.  This will give a value
1146          * between 0 and TQ_MAX_VALUE
1147          */
1148         neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
1149         neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
1150         neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
1151                             BATADV_TQ_LOCAL_WINDOW_SIZE *
1152                             BATADV_TQ_LOCAL_WINDOW_SIZE;
1153         inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
1154         inv_asym_penalty /= neigh_rq_max_cube;
1155         tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;
1156         tq_iface_hop_penalty -= atomic_read(&if_incoming->hop_penalty);
1157
1158         /* penalize if the OGM is forwarded on the same interface. WiFi
1159          * interfaces and other half duplex devices suffer from throughput
1160          * drops as they can't send and receive at the same time.
1161          */
1162         if (if_outgoing && if_incoming == if_outgoing &&
1163             batadv_is_wifi_hardif(if_outgoing))
1164                 tq_iface_hop_penalty = batadv_hop_penalty(tq_iface_hop_penalty,
1165                                                           bat_priv);
1166
1167         combined_tq = batadv_ogm_packet->tq *
1168                       tq_own *
1169                       tq_asym_penalty *
1170                       tq_iface_hop_penalty;
1171         combined_tq /= BATADV_TQ_MAX_VALUE *
1172                        BATADV_TQ_MAX_VALUE *
1173                        BATADV_TQ_MAX_VALUE;
1174         batadv_ogm_packet->tq = combined_tq;
1175
1176         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1177                    "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",
1178                    orig_node->orig, orig_neigh_node->orig, total_count,
1179                    neigh_rq_count, tq_own, tq_asym_penalty,
1180                    tq_iface_hop_penalty, batadv_ogm_packet->tq,
1181                    if_incoming->net_dev->name,
1182                    if_outgoing ? if_outgoing->net_dev->name : "DEFAULT");
1183
1184         /* if link has the minimum required transmission quality
1185          * consider it bidirectional
1186          */
1187         if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
1188                 ret = true;
1189
1190 out:
1191         batadv_neigh_node_put(neigh_node);
1192         return ret;
1193 }
1194
1195 /**
1196  * batadv_iv_ogm_update_seqnos() -  process a batman packet for all interfaces,
1197  *  adjust the sequence number and find out whether it is a duplicate
1198  * @ethhdr: ethernet header of the packet
1199  * @batadv_ogm_packet: OGM packet to be considered
1200  * @if_incoming: interface on which the OGM packet was received
1201  * @if_outgoing: interface for which the retransmission should be considered
1202  *
1203  * Return: duplicate status as enum batadv_dup_status
1204  */
1205 static enum batadv_dup_status
1206 batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
1207                             const struct batadv_ogm_packet *batadv_ogm_packet,
1208                             const struct batadv_hard_iface *if_incoming,
1209                             struct batadv_hard_iface *if_outgoing)
1210 {
1211         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1212         struct batadv_orig_node *orig_node;
1213         struct batadv_orig_ifinfo *orig_ifinfo = NULL;
1214         struct batadv_neigh_node *neigh_node;
1215         struct batadv_neigh_ifinfo *neigh_ifinfo;
1216         bool is_dup;
1217         s32 seq_diff;
1218         bool need_update = false;
1219         int set_mark;
1220         enum batadv_dup_status ret = BATADV_NO_DUP;
1221         u32 seqno = ntohl(batadv_ogm_packet->seqno);
1222         u8 *neigh_addr;
1223         u8 packet_count;
1224         unsigned long *bitmap;
1225
1226         orig_node = batadv_iv_ogm_orig_get(bat_priv, batadv_ogm_packet->orig);
1227         if (!orig_node)
1228                 return BATADV_NO_DUP;
1229
1230         orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
1231         if (WARN_ON(!orig_ifinfo)) {
1232                 batadv_orig_node_put(orig_node);
1233                 return 0;
1234         }
1235
1236         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1237         seq_diff = seqno - orig_ifinfo->last_real_seqno;
1238
1239         /* signalize caller that the packet is to be dropped. */
1240         if (!hlist_empty(&orig_node->neigh_list) &&
1241             batadv_window_protected(bat_priv, seq_diff,
1242                                     BATADV_TQ_LOCAL_WINDOW_SIZE,
1243                                     &orig_ifinfo->batman_seqno_reset, NULL)) {
1244                 ret = BATADV_PROTECTED;
1245                 goto out;
1246         }
1247
1248         rcu_read_lock();
1249         hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
1250                 neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node,
1251                                                        if_outgoing);
1252                 if (!neigh_ifinfo)
1253                         continue;
1254
1255                 neigh_addr = neigh_node->addr;
1256                 is_dup = batadv_test_bit(neigh_ifinfo->bat_iv.real_bits,
1257                                          orig_ifinfo->last_real_seqno,
1258                                          seqno);
1259
1260                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
1261                     neigh_node->if_incoming == if_incoming) {
1262                         set_mark = 1;
1263                         if (is_dup)
1264                                 ret = BATADV_NEIGH_DUP;
1265                 } else {
1266                         set_mark = 0;
1267                         if (is_dup && ret != BATADV_NEIGH_DUP)
1268                                 ret = BATADV_ORIG_DUP;
1269                 }
1270
1271                 /* if the window moved, set the update flag. */
1272                 bitmap = neigh_ifinfo->bat_iv.real_bits;
1273                 need_update |= batadv_bit_get_packet(bat_priv, bitmap,
1274                                                      seq_diff, set_mark);
1275
1276                 packet_count = bitmap_weight(bitmap,
1277                                              BATADV_TQ_LOCAL_WINDOW_SIZE);
1278                 neigh_ifinfo->bat_iv.real_packet_count = packet_count;
1279                 batadv_neigh_ifinfo_put(neigh_ifinfo);
1280         }
1281         rcu_read_unlock();
1282
1283         if (need_update) {
1284                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1285                            "%s updating last_seqno: old %u, new %u\n",
1286                            if_outgoing ? if_outgoing->net_dev->name : "DEFAULT",
1287                            orig_ifinfo->last_real_seqno, seqno);
1288                 orig_ifinfo->last_real_seqno = seqno;
1289         }
1290
1291 out:
1292         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1293         batadv_orig_node_put(orig_node);
1294         batadv_orig_ifinfo_put(orig_ifinfo);
1295         return ret;
1296 }
1297
1298 /**
1299  * batadv_iv_ogm_process_per_outif() - process a batman iv OGM for an outgoing
1300  *  interface
1301  * @skb: the skb containing the OGM
1302  * @ogm_offset: offset from skb->data to start of ogm header
1303  * @orig_node: the (cached) orig node for the originator of this OGM
1304  * @if_incoming: the interface where this packet was received
1305  * @if_outgoing: the interface for which the packet should be considered
1306  */
1307 static void
1308 batadv_iv_ogm_process_per_outif(const struct sk_buff *skb, int ogm_offset,
1309                                 struct batadv_orig_node *orig_node,
1310                                 struct batadv_hard_iface *if_incoming,
1311                                 struct batadv_hard_iface *if_outgoing)
1312 {
1313         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1314         struct batadv_hardif_neigh_node *hardif_neigh = NULL;
1315         struct batadv_neigh_node *router = NULL;
1316         struct batadv_neigh_node *router_router = NULL;
1317         struct batadv_orig_node *orig_neigh_node;
1318         struct batadv_orig_ifinfo *orig_ifinfo;
1319         struct batadv_neigh_node *orig_neigh_router = NULL;
1320         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
1321         struct batadv_ogm_packet *ogm_packet;
1322         enum batadv_dup_status dup_status;
1323         bool is_from_best_next_hop = false;
1324         bool is_single_hop_neigh = false;
1325         bool sameseq, similar_ttl;
1326         struct sk_buff *skb_priv;
1327         struct ethhdr *ethhdr;
1328         u8 *prev_sender;
1329         bool is_bidirect;
1330
1331         /* create a private copy of the skb, as some functions change tq value
1332          * and/or flags.
1333          */
1334         skb_priv = skb_copy(skb, GFP_ATOMIC);
1335         if (!skb_priv)
1336                 return;
1337
1338         ethhdr = eth_hdr(skb_priv);
1339         ogm_packet = (struct batadv_ogm_packet *)(skb_priv->data + ogm_offset);
1340
1341         dup_status = batadv_iv_ogm_update_seqnos(ethhdr, ogm_packet,
1342                                                  if_incoming, if_outgoing);
1343         if (batadv_compare_eth(ethhdr->h_source, ogm_packet->orig))
1344                 is_single_hop_neigh = true;
1345
1346         if (dup_status == BATADV_PROTECTED) {
1347                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1348                            "Drop packet: packet within seqno protection time (sender: %pM)\n",
1349                            ethhdr->h_source);
1350                 goto out;
1351         }
1352
1353         if (ogm_packet->tq == 0) {
1354                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1355                            "Drop packet: originator packet with tq equal 0\n");
1356                 goto out;
1357         }
1358
1359         if (is_single_hop_neigh) {
1360                 hardif_neigh = batadv_hardif_neigh_get(if_incoming,
1361                                                        ethhdr->h_source);
1362                 if (hardif_neigh)
1363                         hardif_neigh->last_seen = jiffies;
1364         }
1365
1366         router = batadv_orig_router_get(orig_node, if_outgoing);
1367         if (router) {
1368                 router_router = batadv_orig_router_get(router->orig_node,
1369                                                        if_outgoing);
1370                 router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing);
1371         }
1372
1373         if ((router_ifinfo && router_ifinfo->bat_iv.tq_avg != 0) &&
1374             (batadv_compare_eth(router->addr, ethhdr->h_source)))
1375                 is_from_best_next_hop = true;
1376
1377         prev_sender = ogm_packet->prev_sender;
1378         /* avoid temporary routing loops */
1379         if (router && router_router &&
1380             (batadv_compare_eth(router->addr, prev_sender)) &&
1381             !(batadv_compare_eth(ogm_packet->orig, prev_sender)) &&
1382             (batadv_compare_eth(router->addr, router_router->addr))) {
1383                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1384                            "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1385                            ethhdr->h_source);
1386                 goto out;
1387         }
1388
1389         if (if_outgoing == BATADV_IF_DEFAULT)
1390                 batadv_tvlv_ogm_receive(bat_priv, ogm_packet, orig_node);
1391
1392         /* if sender is a direct neighbor the sender mac equals
1393          * originator mac
1394          */
1395         if (is_single_hop_neigh)
1396                 orig_neigh_node = orig_node;
1397         else
1398                 orig_neigh_node = batadv_iv_ogm_orig_get(bat_priv,
1399                                                          ethhdr->h_source);
1400
1401         if (!orig_neigh_node)
1402                 goto out;
1403
1404         /* Update nc_nodes of the originator */
1405         batadv_nc_update_nc_node(bat_priv, orig_node, orig_neigh_node,
1406                                  ogm_packet, is_single_hop_neigh);
1407
1408         orig_neigh_router = batadv_orig_router_get(orig_neigh_node,
1409                                                    if_outgoing);
1410
1411         /* drop packet if sender is not a direct neighbor and if we
1412          * don't route towards it
1413          */
1414         if (!is_single_hop_neigh && !orig_neigh_router) {
1415                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1416                            "Drop packet: OGM via unknown neighbor!\n");
1417                 goto out_neigh;
1418         }
1419
1420         is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1421                                             ogm_packet, if_incoming,
1422                                             if_outgoing);
1423
1424         /* update ranking if it is not a duplicate or has the same
1425          * seqno and similar ttl as the non-duplicate
1426          */
1427         orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
1428         if (!orig_ifinfo)
1429                 goto out_neigh;
1430
1431         sameseq = orig_ifinfo->last_real_seqno == ntohl(ogm_packet->seqno);
1432         similar_ttl = (orig_ifinfo->last_ttl - 3) <= ogm_packet->ttl;
1433
1434         if (is_bidirect && (dup_status == BATADV_NO_DUP ||
1435                             (sameseq && similar_ttl))) {
1436                 batadv_iv_ogm_orig_update(bat_priv, orig_node,
1437                                           orig_ifinfo, ethhdr,
1438                                           ogm_packet, if_incoming,
1439                                           if_outgoing, dup_status);
1440         }
1441         batadv_orig_ifinfo_put(orig_ifinfo);
1442
1443         /* only forward for specific interface, not for the default one. */
1444         if (if_outgoing == BATADV_IF_DEFAULT)
1445                 goto out_neigh;
1446
1447         /* is single hop (direct) neighbor */
1448         if (is_single_hop_neigh) {
1449                 /* OGMs from secondary interfaces should only scheduled once
1450                  * per interface where it has been received, not multiple times
1451                  */
1452                 if (ogm_packet->ttl <= 2 &&
1453                     if_incoming != if_outgoing) {
1454                         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1455                                    "Drop packet: OGM from secondary interface and wrong outgoing interface\n");
1456                         goto out_neigh;
1457                 }
1458                 /* mark direct link on incoming interface */
1459                 batadv_iv_ogm_forward(orig_node, ethhdr, ogm_packet,
1460                                       is_single_hop_neigh,
1461                                       is_from_best_next_hop, if_incoming,
1462                                       if_outgoing);
1463
1464                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1465                            "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1466                 goto out_neigh;
1467         }
1468
1469         /* multihop originator */
1470         if (!is_bidirect) {
1471                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1472                            "Drop packet: not received via bidirectional link\n");
1473                 goto out_neigh;
1474         }
1475
1476         if (dup_status == BATADV_NEIGH_DUP) {
1477                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1478                            "Drop packet: duplicate packet received\n");
1479                 goto out_neigh;
1480         }
1481
1482         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1483                    "Forwarding packet: rebroadcast originator packet\n");
1484         batadv_iv_ogm_forward(orig_node, ethhdr, ogm_packet,
1485                               is_single_hop_neigh, is_from_best_next_hop,
1486                               if_incoming, if_outgoing);
1487
1488 out_neigh:
1489         if (orig_neigh_node && !is_single_hop_neigh)
1490                 batadv_orig_node_put(orig_neigh_node);
1491 out:
1492         batadv_neigh_ifinfo_put(router_ifinfo);
1493         batadv_neigh_node_put(router);
1494         batadv_neigh_node_put(router_router);
1495         batadv_neigh_node_put(orig_neigh_router);
1496         batadv_hardif_neigh_put(hardif_neigh);
1497
1498         consume_skb(skb_priv);
1499 }
1500
1501 /**
1502  * batadv_iv_ogm_process_reply() - Check OGM for direct reply and process it
1503  * @ogm_packet: rebroadcast OGM packet to process
1504  * @if_incoming: the interface where this packet was received
1505  * @orig_node: originator which reproadcasted the OGMs
1506  * @if_incoming_seqno: OGM sequence number when rebroadcast was received
1507  */
1508 static void batadv_iv_ogm_process_reply(struct batadv_ogm_packet *ogm_packet,
1509                                         struct batadv_hard_iface *if_incoming,
1510                                         struct batadv_orig_node *orig_node,
1511                                         u32 if_incoming_seqno)
1512 {
1513         struct batadv_orig_ifinfo *orig_ifinfo;
1514         s32 bit_pos;
1515         u8 *weight;
1516
1517         /* neighbor has to indicate direct link and it has to
1518          * come via the corresponding interface
1519          */
1520         if (!(ogm_packet->flags & BATADV_DIRECTLINK))
1521                 return;
1522
1523         if (!batadv_compare_eth(if_incoming->net_dev->dev_addr,
1524                                 ogm_packet->orig))
1525                 return;
1526
1527         orig_ifinfo = batadv_orig_ifinfo_get(orig_node, if_incoming);
1528         if (!orig_ifinfo)
1529                 return;
1530
1531         /* save packet seqno for bidirectional check */
1532         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1533         bit_pos = if_incoming_seqno - 2;
1534         bit_pos -= ntohl(ogm_packet->seqno);
1535         batadv_set_bit(orig_ifinfo->bat_iv.bcast_own, bit_pos);
1536         weight = &orig_ifinfo->bat_iv.bcast_own_sum;
1537         *weight = bitmap_weight(orig_ifinfo->bat_iv.bcast_own,
1538                                 BATADV_TQ_LOCAL_WINDOW_SIZE);
1539         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1540
1541         batadv_orig_ifinfo_put(orig_ifinfo);
1542 }
1543
1544 /**
1545  * batadv_iv_ogm_process() - process an incoming batman iv OGM
1546  * @skb: the skb containing the OGM
1547  * @ogm_offset: offset to the OGM which should be processed (for aggregates)
1548  * @if_incoming: the interface where this packet was received
1549  */
1550 static void batadv_iv_ogm_process(const struct sk_buff *skb, int ogm_offset,
1551                                   struct batadv_hard_iface *if_incoming)
1552 {
1553         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1554         struct batadv_orig_node *orig_neigh_node, *orig_node;
1555         struct batadv_hard_iface *hard_iface;
1556         struct batadv_ogm_packet *ogm_packet;
1557         u32 if_incoming_seqno;
1558         bool has_directlink_flag;
1559         struct ethhdr *ethhdr;
1560         bool is_my_oldorig = false;
1561         bool is_my_addr = false;
1562         bool is_my_orig = false;
1563
1564         ogm_packet = (struct batadv_ogm_packet *)(skb->data + ogm_offset);
1565         ethhdr = eth_hdr(skb);
1566
1567         /* Silently drop when the batman packet is actually not a
1568          * correct packet.
1569          *
1570          * This might happen if a packet is padded (e.g. Ethernet has a
1571          * minimum frame length of 64 byte) and the aggregation interprets
1572          * it as an additional length.
1573          *
1574          * TODO: A more sane solution would be to have a bit in the
1575          * batadv_ogm_packet to detect whether the packet is the last
1576          * packet in an aggregation.  Here we expect that the padding
1577          * is always zero (or not 0x01)
1578          */
1579         if (ogm_packet->packet_type != BATADV_IV_OGM)
1580                 return;
1581
1582         /* could be changed by schedule_own_packet() */
1583         if_incoming_seqno = atomic_read(&if_incoming->bat_iv.ogm_seqno);
1584
1585         if (ogm_packet->flags & BATADV_DIRECTLINK)
1586                 has_directlink_flag = true;
1587         else
1588                 has_directlink_flag = false;
1589
1590         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1591                    "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",
1592                    ethhdr->h_source, if_incoming->net_dev->name,
1593                    if_incoming->net_dev->dev_addr, ogm_packet->orig,
1594                    ogm_packet->prev_sender, ntohl(ogm_packet->seqno),
1595                    ogm_packet->tq, ogm_packet->ttl,
1596                    ogm_packet->version, has_directlink_flag);
1597
1598         rcu_read_lock();
1599         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1600                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
1601                         continue;
1602
1603                 if (hard_iface->soft_iface != if_incoming->soft_iface)
1604                         continue;
1605
1606                 if (batadv_compare_eth(ethhdr->h_source,
1607                                        hard_iface->net_dev->dev_addr))
1608                         is_my_addr = true;
1609
1610                 if (batadv_compare_eth(ogm_packet->orig,
1611                                        hard_iface->net_dev->dev_addr))
1612                         is_my_orig = true;
1613
1614                 if (batadv_compare_eth(ogm_packet->prev_sender,
1615                                        hard_iface->net_dev->dev_addr))
1616                         is_my_oldorig = true;
1617         }
1618         rcu_read_unlock();
1619
1620         if (is_my_addr) {
1621                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1622                            "Drop packet: received my own broadcast (sender: %pM)\n",
1623                            ethhdr->h_source);
1624                 return;
1625         }
1626
1627         if (is_my_orig) {
1628                 orig_neigh_node = batadv_iv_ogm_orig_get(bat_priv,
1629                                                          ethhdr->h_source);
1630                 if (!orig_neigh_node)
1631                         return;
1632
1633                 batadv_iv_ogm_process_reply(ogm_packet, if_incoming,
1634                                             orig_neigh_node, if_incoming_seqno);
1635
1636                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1637                            "Drop packet: originator packet from myself (via neighbor)\n");
1638                 batadv_orig_node_put(orig_neigh_node);
1639                 return;
1640         }
1641
1642         if (is_my_oldorig) {
1643                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1644                            "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1645                            ethhdr->h_source);
1646                 return;
1647         }
1648
1649         if (ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) {
1650                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1651                            "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1652                            ethhdr->h_source);
1653                 return;
1654         }
1655
1656         orig_node = batadv_iv_ogm_orig_get(bat_priv, ogm_packet->orig);
1657         if (!orig_node)
1658                 return;
1659
1660         batadv_iv_ogm_process_per_outif(skb, ogm_offset, orig_node,
1661                                         if_incoming, BATADV_IF_DEFAULT);
1662
1663         rcu_read_lock();
1664         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1665                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
1666                         continue;
1667
1668                 if (hard_iface->soft_iface != bat_priv->soft_iface)
1669                         continue;
1670
1671                 if (!kref_get_unless_zero(&hard_iface->refcount))
1672                         continue;
1673
1674                 batadv_iv_ogm_process_per_outif(skb, ogm_offset, orig_node,
1675                                                 if_incoming, hard_iface);
1676
1677                 batadv_hardif_put(hard_iface);
1678         }
1679         rcu_read_unlock();
1680
1681         batadv_orig_node_put(orig_node);
1682 }
1683
1684 static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work)
1685 {
1686         struct delayed_work *delayed_work;
1687         struct batadv_forw_packet *forw_packet;
1688         struct batadv_priv *bat_priv;
1689         bool dropped = false;
1690
1691         delayed_work = to_delayed_work(work);
1692         forw_packet = container_of(delayed_work, struct batadv_forw_packet,
1693                                    delayed_work);
1694         bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface);
1695
1696         if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) {
1697                 dropped = true;
1698                 goto out;
1699         }
1700
1701         batadv_iv_ogm_emit(forw_packet);
1702
1703         /* we have to have at least one packet in the queue to determine the
1704          * queues wake up time unless we are shutting down.
1705          *
1706          * only re-schedule if this is the "original" copy, e.g. the OGM of the
1707          * primary interface should only be rescheduled once per period, but
1708          * this function will be called for the forw_packet instances of the
1709          * other secondary interfaces as well.
1710          */
1711         if (forw_packet->own &&
1712             forw_packet->if_incoming == forw_packet->if_outgoing)
1713                 batadv_iv_ogm_schedule(forw_packet->if_incoming);
1714
1715 out:
1716         /* do we get something for free()? */
1717         if (batadv_forw_packet_steal(forw_packet,
1718                                      &bat_priv->forw_bat_list_lock))
1719                 batadv_forw_packet_free(forw_packet, dropped);
1720 }
1721
1722 static int batadv_iv_ogm_receive(struct sk_buff *skb,
1723                                  struct batadv_hard_iface *if_incoming)
1724 {
1725         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1726         struct batadv_ogm_packet *ogm_packet;
1727         u8 *packet_pos;
1728         int ogm_offset;
1729         bool res;
1730         int ret = NET_RX_DROP;
1731
1732         res = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
1733         if (!res)
1734                 goto free_skb;
1735
1736         /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1737          * that does not have B.A.T.M.A.N. IV enabled ?
1738          */
1739         if (bat_priv->algo_ops->iface.enable != batadv_iv_ogm_iface_enable)
1740                 goto free_skb;
1741
1742         batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
1743         batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
1744                            skb->len + ETH_HLEN);
1745
1746         ogm_offset = 0;
1747         ogm_packet = (struct batadv_ogm_packet *)skb->data;
1748
1749         /* unpack the aggregated packets and process them one by one */
1750         while (batadv_iv_ogm_aggr_packet(ogm_offset, skb_headlen(skb),
1751                                          ogm_packet)) {
1752                 batadv_iv_ogm_process(skb, ogm_offset, if_incoming);
1753
1754                 ogm_offset += BATADV_OGM_HLEN;
1755                 ogm_offset += ntohs(ogm_packet->tvlv_len);
1756
1757                 packet_pos = skb->data + ogm_offset;
1758                 ogm_packet = (struct batadv_ogm_packet *)packet_pos;
1759         }
1760
1761         ret = NET_RX_SUCCESS;
1762
1763 free_skb:
1764         if (ret == NET_RX_SUCCESS)
1765                 consume_skb(skb);
1766         else
1767                 kfree_skb(skb);
1768
1769         return ret;
1770 }
1771
1772 /**
1773  * batadv_iv_ogm_neigh_get_tq_avg() - Get the TQ average for a neighbour on a
1774  *  given outgoing interface.
1775  * @neigh_node: Neighbour of interest
1776  * @if_outgoing: Outgoing interface of interest
1777  * @tq_avg: Pointer of where to store the TQ average
1778  *
1779  * Return: False if no average TQ available, otherwise true.
1780  */
1781 static bool
1782 batadv_iv_ogm_neigh_get_tq_avg(struct batadv_neigh_node *neigh_node,
1783                                struct batadv_hard_iface *if_outgoing,
1784                                u8 *tq_avg)
1785 {
1786         struct batadv_neigh_ifinfo *n_ifinfo;
1787
1788         n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
1789         if (!n_ifinfo)
1790                 return false;
1791
1792         *tq_avg = n_ifinfo->bat_iv.tq_avg;
1793         batadv_neigh_ifinfo_put(n_ifinfo);
1794
1795         return true;
1796 }
1797
1798 /**
1799  * batadv_iv_ogm_orig_dump_subentry() - Dump an originator subentry into a
1800  *  message
1801  * @msg: Netlink message to dump into
1802  * @portid: Port making netlink request
1803  * @seq: Sequence number of netlink message
1804  * @bat_priv: The bat priv with all the soft interface information
1805  * @if_outgoing: Limit dump to entries with this outgoing interface
1806  * @orig_node: Originator to dump
1807  * @neigh_node: Single hops neighbour
1808  * @best: Is the best originator
1809  *
1810  * Return: Error code, or 0 on success
1811  */
1812 static int
1813 batadv_iv_ogm_orig_dump_subentry(struct sk_buff *msg, u32 portid, u32 seq,
1814                                  struct batadv_priv *bat_priv,
1815                                  struct batadv_hard_iface *if_outgoing,
1816                                  struct batadv_orig_node *orig_node,
1817                                  struct batadv_neigh_node *neigh_node,
1818                                  bool best)
1819 {
1820         void *hdr;
1821         u8 tq_avg;
1822         unsigned int last_seen_msecs;
1823
1824         last_seen_msecs = jiffies_to_msecs(jiffies - orig_node->last_seen);
1825
1826         if (!batadv_iv_ogm_neigh_get_tq_avg(neigh_node, if_outgoing, &tq_avg))
1827                 return 0;
1828
1829         if (if_outgoing != BATADV_IF_DEFAULT &&
1830             if_outgoing != neigh_node->if_incoming)
1831                 return 0;
1832
1833         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
1834                           NLM_F_MULTI, BATADV_CMD_GET_ORIGINATORS);
1835         if (!hdr)
1836                 return -ENOBUFS;
1837
1838         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
1839                     orig_node->orig) ||
1840             nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
1841                     neigh_node->addr) ||
1842             nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
1843                            neigh_node->if_incoming->net_dev->name) ||
1844             nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
1845                         neigh_node->if_incoming->net_dev->ifindex) ||
1846             nla_put_u8(msg, BATADV_ATTR_TQ, tq_avg) ||
1847             nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
1848                         last_seen_msecs))
1849                 goto nla_put_failure;
1850
1851         if (best && nla_put_flag(msg, BATADV_ATTR_FLAG_BEST))
1852                 goto nla_put_failure;
1853
1854         genlmsg_end(msg, hdr);
1855         return 0;
1856
1857  nla_put_failure:
1858         genlmsg_cancel(msg, hdr);
1859         return -EMSGSIZE;
1860 }
1861
1862 /**
1863  * batadv_iv_ogm_orig_dump_entry() - Dump an originator entry into a message
1864  * @msg: Netlink message to dump into
1865  * @portid: Port making netlink request
1866  * @seq: Sequence number of netlink message
1867  * @bat_priv: The bat priv with all the soft interface information
1868  * @if_outgoing: Limit dump to entries with this outgoing interface
1869  * @orig_node: Originator to dump
1870  * @sub_s: Number of sub entries to skip
1871  *
1872  * This function assumes the caller holds rcu_read_lock().
1873  *
1874  * Return: Error code, or 0 on success
1875  */
1876 static int
1877 batadv_iv_ogm_orig_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
1878                               struct batadv_priv *bat_priv,
1879                               struct batadv_hard_iface *if_outgoing,
1880                               struct batadv_orig_node *orig_node, int *sub_s)
1881 {
1882         struct batadv_neigh_node *neigh_node_best;
1883         struct batadv_neigh_node *neigh_node;
1884         int sub = 0;
1885         bool best;
1886         u8 tq_avg_best;
1887
1888         neigh_node_best = batadv_orig_router_get(orig_node, if_outgoing);
1889         if (!neigh_node_best)
1890                 goto out;
1891
1892         if (!batadv_iv_ogm_neigh_get_tq_avg(neigh_node_best, if_outgoing,
1893                                             &tq_avg_best))
1894                 goto out;
1895
1896         if (tq_avg_best == 0)
1897                 goto out;
1898
1899         hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
1900                 if (sub++ < *sub_s)
1901                         continue;
1902
1903                 best = (neigh_node == neigh_node_best);
1904
1905                 if (batadv_iv_ogm_orig_dump_subentry(msg, portid, seq,
1906                                                      bat_priv, if_outgoing,
1907                                                      orig_node, neigh_node,
1908                                                      best)) {
1909                         batadv_neigh_node_put(neigh_node_best);
1910
1911                         *sub_s = sub - 1;
1912                         return -EMSGSIZE;
1913                 }
1914         }
1915
1916  out:
1917         batadv_neigh_node_put(neigh_node_best);
1918
1919         *sub_s = 0;
1920         return 0;
1921 }
1922
1923 /**
1924  * batadv_iv_ogm_orig_dump_bucket() - Dump an originator bucket into a
1925  *  message
1926  * @msg: Netlink message to dump into
1927  * @portid: Port making netlink request
1928  * @seq: Sequence number of netlink message
1929  * @bat_priv: The bat priv with all the soft interface information
1930  * @if_outgoing: Limit dump to entries with this outgoing interface
1931  * @head: Bucket to be dumped
1932  * @idx_s: Number of entries to be skipped
1933  * @sub: Number of sub entries to be skipped
1934  *
1935  * Return: Error code, or 0 on success
1936  */
1937 static int
1938 batadv_iv_ogm_orig_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
1939                                struct batadv_priv *bat_priv,
1940                                struct batadv_hard_iface *if_outgoing,
1941                                struct hlist_head *head, int *idx_s, int *sub)
1942 {
1943         struct batadv_orig_node *orig_node;
1944         int idx = 0;
1945
1946         rcu_read_lock();
1947         hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
1948                 if (idx++ < *idx_s)
1949                         continue;
1950
1951                 if (batadv_iv_ogm_orig_dump_entry(msg, portid, seq, bat_priv,
1952                                                   if_outgoing, orig_node,
1953                                                   sub)) {
1954                         rcu_read_unlock();
1955                         *idx_s = idx - 1;
1956                         return -EMSGSIZE;
1957                 }
1958         }
1959         rcu_read_unlock();
1960
1961         *idx_s = 0;
1962         *sub = 0;
1963         return 0;
1964 }
1965
1966 /**
1967  * batadv_iv_ogm_orig_dump() - Dump the originators into a message
1968  * @msg: Netlink message to dump into
1969  * @cb: Control block containing additional options
1970  * @bat_priv: The bat priv with all the soft interface information
1971  * @if_outgoing: Limit dump to entries with this outgoing interface
1972  */
1973 static void
1974 batadv_iv_ogm_orig_dump(struct sk_buff *msg, struct netlink_callback *cb,
1975                         struct batadv_priv *bat_priv,
1976                         struct batadv_hard_iface *if_outgoing)
1977 {
1978         struct batadv_hashtable *hash = bat_priv->orig_hash;
1979         struct hlist_head *head;
1980         int bucket = cb->args[0];
1981         int idx = cb->args[1];
1982         int sub = cb->args[2];
1983         int portid = NETLINK_CB(cb->skb).portid;
1984
1985         while (bucket < hash->size) {
1986                 head = &hash->table[bucket];
1987
1988                 if (batadv_iv_ogm_orig_dump_bucket(msg, portid,
1989                                                    cb->nlh->nlmsg_seq,
1990                                                    bat_priv, if_outgoing, head,
1991                                                    &idx, &sub))
1992                         break;
1993
1994                 bucket++;
1995         }
1996
1997         cb->args[0] = bucket;
1998         cb->args[1] = idx;
1999         cb->args[2] = sub;
2000 }
2001
2002 /**
2003  * batadv_iv_ogm_neigh_diff() - calculate tq difference of two neighbors
2004  * @neigh1: the first neighbor object of the comparison
2005  * @if_outgoing1: outgoing interface for the first neighbor
2006  * @neigh2: the second neighbor object of the comparison
2007  * @if_outgoing2: outgoing interface for the second neighbor
2008  * @diff: pointer to integer receiving the calculated difference
2009  *
2010  * The content of *@diff is only valid when this function returns true.
2011  * It is less, equal to or greater than 0 if the metric via neigh1 is lower,
2012  * the same as or higher than the metric via neigh2
2013  *
2014  * Return: true when the difference could be calculated, false otherwise
2015  */
2016 static bool batadv_iv_ogm_neigh_diff(struct batadv_neigh_node *neigh1,
2017                                      struct batadv_hard_iface *if_outgoing1,
2018                                      struct batadv_neigh_node *neigh2,
2019                                      struct batadv_hard_iface *if_outgoing2,
2020                                      int *diff)
2021 {
2022         struct batadv_neigh_ifinfo *neigh1_ifinfo, *neigh2_ifinfo;
2023         u8 tq1, tq2;
2024         bool ret = true;
2025
2026         neigh1_ifinfo = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
2027         neigh2_ifinfo = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
2028
2029         if (!neigh1_ifinfo || !neigh2_ifinfo) {
2030                 ret = false;
2031                 goto out;
2032         }
2033
2034         tq1 = neigh1_ifinfo->bat_iv.tq_avg;
2035         tq2 = neigh2_ifinfo->bat_iv.tq_avg;
2036         *diff = (int)tq1 - (int)tq2;
2037
2038 out:
2039         batadv_neigh_ifinfo_put(neigh1_ifinfo);
2040         batadv_neigh_ifinfo_put(neigh2_ifinfo);
2041
2042         return ret;
2043 }
2044
2045 /**
2046  * batadv_iv_ogm_neigh_dump_neigh() - Dump a neighbour into a netlink message
2047  * @msg: Netlink message to dump into
2048  * @portid: Port making netlink request
2049  * @seq: Sequence number of netlink message
2050  * @hardif_neigh: Neighbour to be dumped
2051  *
2052  * Return: Error code, or 0 on success
2053  */
2054 static int
2055 batadv_iv_ogm_neigh_dump_neigh(struct sk_buff *msg, u32 portid, u32 seq,
2056                                struct batadv_hardif_neigh_node *hardif_neigh)
2057 {
2058         void *hdr;
2059         unsigned int last_seen_msecs;
2060
2061         last_seen_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen);
2062
2063         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
2064                           NLM_F_MULTI, BATADV_CMD_GET_NEIGHBORS);
2065         if (!hdr)
2066                 return -ENOBUFS;
2067
2068         if (nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
2069                     hardif_neigh->addr) ||
2070             nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
2071                            hardif_neigh->if_incoming->net_dev->name) ||
2072             nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
2073                         hardif_neigh->if_incoming->net_dev->ifindex) ||
2074             nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
2075                         last_seen_msecs))
2076                 goto nla_put_failure;
2077
2078         genlmsg_end(msg, hdr);
2079         return 0;
2080
2081  nla_put_failure:
2082         genlmsg_cancel(msg, hdr);
2083         return -EMSGSIZE;
2084 }
2085
2086 /**
2087  * batadv_iv_ogm_neigh_dump_hardif() - Dump the neighbours of a hard interface
2088  *  into a message
2089  * @msg: Netlink message to dump into
2090  * @portid: Port making netlink request
2091  * @seq: Sequence number of netlink message
2092  * @bat_priv: The bat priv with all the soft interface information
2093  * @hard_iface: Hard interface to dump the neighbours for
2094  * @idx_s: Number of entries to skip
2095  *
2096  * This function assumes the caller holds rcu_read_lock().
2097  *
2098  * Return: Error code, or 0 on success
2099  */
2100 static int
2101 batadv_iv_ogm_neigh_dump_hardif(struct sk_buff *msg, u32 portid, u32 seq,
2102                                 struct batadv_priv *bat_priv,
2103                                 struct batadv_hard_iface *hard_iface,
2104                                 int *idx_s)
2105 {
2106         struct batadv_hardif_neigh_node *hardif_neigh;
2107         int idx = 0;
2108
2109         hlist_for_each_entry_rcu(hardif_neigh,
2110                                  &hard_iface->neigh_list, list) {
2111                 if (idx++ < *idx_s)
2112                         continue;
2113
2114                 if (batadv_iv_ogm_neigh_dump_neigh(msg, portid, seq,
2115                                                    hardif_neigh)) {
2116                         *idx_s = idx - 1;
2117                         return -EMSGSIZE;
2118                 }
2119         }
2120
2121         *idx_s = 0;
2122         return 0;
2123 }
2124
2125 /**
2126  * batadv_iv_ogm_neigh_dump() - Dump the neighbours into a message
2127  * @msg: Netlink message to dump into
2128  * @cb: Control block containing additional options
2129  * @bat_priv: The bat priv with all the soft interface information
2130  * @single_hardif: Limit dump to this hard interface
2131  */
2132 static void
2133 batadv_iv_ogm_neigh_dump(struct sk_buff *msg, struct netlink_callback *cb,
2134                          struct batadv_priv *bat_priv,
2135                          struct batadv_hard_iface *single_hardif)
2136 {
2137         struct batadv_hard_iface *hard_iface;
2138         int i_hardif = 0;
2139         int i_hardif_s = cb->args[0];
2140         int idx = cb->args[1];
2141         int portid = NETLINK_CB(cb->skb).portid;
2142
2143         rcu_read_lock();
2144         if (single_hardif) {
2145                 if (i_hardif_s == 0) {
2146                         if (batadv_iv_ogm_neigh_dump_hardif(msg, portid,
2147                                                             cb->nlh->nlmsg_seq,
2148                                                             bat_priv,
2149                                                             single_hardif,
2150                                                             &idx) == 0)
2151                                 i_hardif++;
2152                 }
2153         } else {
2154                 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list,
2155                                         list) {
2156                         if (hard_iface->soft_iface != bat_priv->soft_iface)
2157                                 continue;
2158
2159                         if (i_hardif++ < i_hardif_s)
2160                                 continue;
2161
2162                         if (batadv_iv_ogm_neigh_dump_hardif(msg, portid,
2163                                                             cb->nlh->nlmsg_seq,
2164                                                             bat_priv,
2165                                                             hard_iface, &idx)) {
2166                                 i_hardif--;
2167                                 break;
2168                         }
2169                 }
2170         }
2171         rcu_read_unlock();
2172
2173         cb->args[0] = i_hardif;
2174         cb->args[1] = idx;
2175 }
2176
2177 /**
2178  * batadv_iv_ogm_neigh_cmp() - compare the metrics of two neighbors
2179  * @neigh1: the first neighbor object of the comparison
2180  * @if_outgoing1: outgoing interface for the first neighbor
2181  * @neigh2: the second neighbor object of the comparison
2182  * @if_outgoing2: outgoing interface for the second neighbor
2183  *
2184  * Return: a value less, equal to or greater than 0 if the metric via neigh1 is
2185  * lower, the same as or higher than the metric via neigh2
2186  */
2187 static int batadv_iv_ogm_neigh_cmp(struct batadv_neigh_node *neigh1,
2188                                    struct batadv_hard_iface *if_outgoing1,
2189                                    struct batadv_neigh_node *neigh2,
2190                                    struct batadv_hard_iface *if_outgoing2)
2191 {
2192         bool ret;
2193         int diff;
2194
2195         ret = batadv_iv_ogm_neigh_diff(neigh1, if_outgoing1, neigh2,
2196                                        if_outgoing2, &diff);
2197         if (!ret)
2198                 return 0;
2199
2200         return diff;
2201 }
2202
2203 /**
2204  * batadv_iv_ogm_neigh_is_sob() - check if neigh1 is similarly good or better
2205  *  than neigh2 from the metric prospective
2206  * @neigh1: the first neighbor object of the comparison
2207  * @if_outgoing1: outgoing interface for the first neighbor
2208  * @neigh2: the second neighbor object of the comparison
2209  * @if_outgoing2: outgoing interface for the second neighbor
2210  *
2211  * Return: true if the metric via neigh1 is equally good or better than
2212  * the metric via neigh2, false otherwise.
2213  */
2214 static bool
2215 batadv_iv_ogm_neigh_is_sob(struct batadv_neigh_node *neigh1,
2216                            struct batadv_hard_iface *if_outgoing1,
2217                            struct batadv_neigh_node *neigh2,
2218                            struct batadv_hard_iface *if_outgoing2)
2219 {
2220         bool ret;
2221         int diff;
2222
2223         ret = batadv_iv_ogm_neigh_diff(neigh1, if_outgoing1, neigh2,
2224                                        if_outgoing2, &diff);
2225         if (!ret)
2226                 return false;
2227
2228         ret = diff > -BATADV_TQ_SIMILARITY_THRESHOLD;
2229         return ret;
2230 }
2231
2232 static void batadv_iv_iface_enabled(struct batadv_hard_iface *hard_iface)
2233 {
2234         /* begin scheduling originator messages on that interface */
2235         batadv_iv_ogm_schedule(hard_iface);
2236 }
2237
2238 /**
2239  * batadv_iv_init_sel_class() - initialize GW selection class
2240  * @bat_priv: the bat priv with all the soft interface information
2241  */
2242 static void batadv_iv_init_sel_class(struct batadv_priv *bat_priv)
2243 {
2244         /* set default TQ difference threshold to 20 */
2245         atomic_set(&bat_priv->gw.sel_class, 20);
2246 }
2247
2248 static struct batadv_gw_node *
2249 batadv_iv_gw_get_best_gw_node(struct batadv_priv *bat_priv)
2250 {
2251         struct batadv_neigh_node *router;
2252         struct batadv_neigh_ifinfo *router_ifinfo;
2253         struct batadv_gw_node *gw_node, *curr_gw = NULL;
2254         u64 max_gw_factor = 0;
2255         u64 tmp_gw_factor = 0;
2256         u8 max_tq = 0;
2257         u8 tq_avg;
2258         struct batadv_orig_node *orig_node;
2259
2260         rcu_read_lock();
2261         hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
2262                 orig_node = gw_node->orig_node;
2263                 router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
2264                 if (!router)
2265                         continue;
2266
2267                 router_ifinfo = batadv_neigh_ifinfo_get(router,
2268                                                         BATADV_IF_DEFAULT);
2269                 if (!router_ifinfo)
2270                         goto next;
2271
2272                 if (!kref_get_unless_zero(&gw_node->refcount))
2273                         goto next;
2274
2275                 tq_avg = router_ifinfo->bat_iv.tq_avg;
2276
2277                 switch (atomic_read(&bat_priv->gw.sel_class)) {
2278                 case 1: /* fast connection */
2279                         tmp_gw_factor = tq_avg * tq_avg;
2280                         tmp_gw_factor *= gw_node->bandwidth_down;
2281                         tmp_gw_factor *= 100 * 100;
2282                         tmp_gw_factor >>= 18;
2283
2284                         if (tmp_gw_factor > max_gw_factor ||
2285                             (tmp_gw_factor == max_gw_factor &&
2286                              tq_avg > max_tq)) {
2287                                 batadv_gw_node_put(curr_gw);
2288                                 curr_gw = gw_node;
2289                                 kref_get(&curr_gw->refcount);
2290                         }
2291                         break;
2292
2293                 default: /* 2:  stable connection (use best statistic)
2294                           * 3:  fast-switch (use best statistic but change as
2295                           *     soon as a better gateway appears)
2296                           * XX: late-switch (use best statistic but change as
2297                           *     soon as a better gateway appears which has
2298                           *     $routing_class more tq points)
2299                           */
2300                         if (tq_avg > max_tq) {
2301                                 batadv_gw_node_put(curr_gw);
2302                                 curr_gw = gw_node;
2303                                 kref_get(&curr_gw->refcount);
2304                         }
2305                         break;
2306                 }
2307
2308                 if (tq_avg > max_tq)
2309                         max_tq = tq_avg;
2310
2311                 if (tmp_gw_factor > max_gw_factor)
2312                         max_gw_factor = tmp_gw_factor;
2313
2314                 batadv_gw_node_put(gw_node);
2315
2316 next:
2317                 batadv_neigh_node_put(router);
2318                 batadv_neigh_ifinfo_put(router_ifinfo);
2319         }
2320         rcu_read_unlock();
2321
2322         return curr_gw;
2323 }
2324
2325 static bool batadv_iv_gw_is_eligible(struct batadv_priv *bat_priv,
2326                                      struct batadv_orig_node *curr_gw_orig,
2327                                      struct batadv_orig_node *orig_node)
2328 {
2329         struct batadv_neigh_ifinfo *router_orig_ifinfo = NULL;
2330         struct batadv_neigh_ifinfo *router_gw_ifinfo = NULL;
2331         struct batadv_neigh_node *router_gw = NULL;
2332         struct batadv_neigh_node *router_orig = NULL;
2333         u8 gw_tq_avg, orig_tq_avg;
2334         bool ret = false;
2335
2336         /* dynamic re-election is performed only on fast or late switch */
2337         if (atomic_read(&bat_priv->gw.sel_class) <= 2)
2338                 return false;
2339
2340         router_gw = batadv_orig_router_get(curr_gw_orig, BATADV_IF_DEFAULT);
2341         if (!router_gw) {
2342                 ret = true;
2343                 goto out;
2344         }
2345
2346         router_gw_ifinfo = batadv_neigh_ifinfo_get(router_gw,
2347                                                    BATADV_IF_DEFAULT);
2348         if (!router_gw_ifinfo) {
2349                 ret = true;
2350                 goto out;
2351         }
2352
2353         router_orig = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
2354         if (!router_orig)
2355                 goto out;
2356
2357         router_orig_ifinfo = batadv_neigh_ifinfo_get(router_orig,
2358                                                      BATADV_IF_DEFAULT);
2359         if (!router_orig_ifinfo)
2360                 goto out;
2361
2362         gw_tq_avg = router_gw_ifinfo->bat_iv.tq_avg;
2363         orig_tq_avg = router_orig_ifinfo->bat_iv.tq_avg;
2364
2365         /* the TQ value has to be better */
2366         if (orig_tq_avg < gw_tq_avg)
2367                 goto out;
2368
2369         /* if the routing class is greater than 3 the value tells us how much
2370          * greater the TQ value of the new gateway must be
2371          */
2372         if ((atomic_read(&bat_priv->gw.sel_class) > 3) &&
2373             (orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw.sel_class)))
2374                 goto out;
2375
2376         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
2377                    "Restarting gateway selection: better gateway found (tq curr: %i, tq new: %i)\n",
2378                    gw_tq_avg, orig_tq_avg);
2379
2380         ret = true;
2381 out:
2382         batadv_neigh_ifinfo_put(router_gw_ifinfo);
2383         batadv_neigh_ifinfo_put(router_orig_ifinfo);
2384         batadv_neigh_node_put(router_gw);
2385         batadv_neigh_node_put(router_orig);
2386
2387         return ret;
2388 }
2389
2390 /**
2391  * batadv_iv_gw_dump_entry() - Dump a gateway into a message
2392  * @msg: Netlink message to dump into
2393  * @portid: Port making netlink request
2394  * @cb: Control block containing additional options
2395  * @bat_priv: The bat priv with all the soft interface information
2396  * @gw_node: Gateway to be dumped
2397  *
2398  * Return: Error code, or 0 on success
2399  */
2400 static int batadv_iv_gw_dump_entry(struct sk_buff *msg, u32 portid,
2401                                    struct netlink_callback *cb,
2402                                    struct batadv_priv *bat_priv,
2403                                    struct batadv_gw_node *gw_node)
2404 {
2405         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
2406         struct batadv_neigh_node *router;
2407         struct batadv_gw_node *curr_gw = NULL;
2408         int ret = 0;
2409         void *hdr;
2410
2411         router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
2412         if (!router)
2413                 goto out;
2414
2415         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
2416         if (!router_ifinfo)
2417                 goto out;
2418
2419         curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
2420
2421         hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
2422                           &batadv_netlink_family, NLM_F_MULTI,
2423                           BATADV_CMD_GET_GATEWAYS);
2424         if (!hdr) {
2425                 ret = -ENOBUFS;
2426                 goto out;
2427         }
2428
2429         genl_dump_check_consistent(cb, hdr);
2430
2431         ret = -EMSGSIZE;
2432
2433         if (curr_gw == gw_node)
2434                 if (nla_put_flag(msg, BATADV_ATTR_FLAG_BEST)) {
2435                         genlmsg_cancel(msg, hdr);
2436                         goto out;
2437                 }
2438
2439         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
2440                     gw_node->orig_node->orig) ||
2441             nla_put_u8(msg, BATADV_ATTR_TQ, router_ifinfo->bat_iv.tq_avg) ||
2442             nla_put(msg, BATADV_ATTR_ROUTER, ETH_ALEN,
2443                     router->addr) ||
2444             nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
2445                            router->if_incoming->net_dev->name) ||
2446             nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
2447                         router->if_incoming->net_dev->ifindex) ||
2448             nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_DOWN,
2449                         gw_node->bandwidth_down) ||
2450             nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_UP,
2451                         gw_node->bandwidth_up)) {
2452                 genlmsg_cancel(msg, hdr);
2453                 goto out;
2454         }
2455
2456         genlmsg_end(msg, hdr);
2457         ret = 0;
2458
2459 out:
2460         batadv_gw_node_put(curr_gw);
2461         batadv_neigh_ifinfo_put(router_ifinfo);
2462         batadv_neigh_node_put(router);
2463         return ret;
2464 }
2465
2466 /**
2467  * batadv_iv_gw_dump() - Dump gateways into a message
2468  * @msg: Netlink message to dump into
2469  * @cb: Control block containing additional options
2470  * @bat_priv: The bat priv with all the soft interface information
2471  */
2472 static void batadv_iv_gw_dump(struct sk_buff *msg, struct netlink_callback *cb,
2473                               struct batadv_priv *bat_priv)
2474 {
2475         int portid = NETLINK_CB(cb->skb).portid;
2476         struct batadv_gw_node *gw_node;
2477         int idx_skip = cb->args[0];
2478         int idx = 0;
2479
2480         spin_lock_bh(&bat_priv->gw.list_lock);
2481         cb->seq = bat_priv->gw.generation << 1 | 1;
2482
2483         hlist_for_each_entry(gw_node, &bat_priv->gw.gateway_list, list) {
2484                 if (idx++ < idx_skip)
2485                         continue;
2486
2487                 if (batadv_iv_gw_dump_entry(msg, portid, cb, bat_priv,
2488                                             gw_node)) {
2489                         idx_skip = idx - 1;
2490                         goto unlock;
2491                 }
2492         }
2493
2494         idx_skip = idx;
2495 unlock:
2496         spin_unlock_bh(&bat_priv->gw.list_lock);
2497
2498         cb->args[0] = idx_skip;
2499 }
2500
2501 static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
2502         .name = "BATMAN_IV",
2503         .iface = {
2504                 .enable = batadv_iv_ogm_iface_enable,
2505                 .enabled = batadv_iv_iface_enabled,
2506                 .disable = batadv_iv_ogm_iface_disable,
2507                 .update_mac = batadv_iv_ogm_iface_update_mac,
2508                 .primary_set = batadv_iv_ogm_primary_iface_set,
2509         },
2510         .neigh = {
2511                 .cmp = batadv_iv_ogm_neigh_cmp,
2512                 .is_similar_or_better = batadv_iv_ogm_neigh_is_sob,
2513                 .dump = batadv_iv_ogm_neigh_dump,
2514         },
2515         .orig = {
2516                 .dump = batadv_iv_ogm_orig_dump,
2517         },
2518         .gw = {
2519                 .init_sel_class = batadv_iv_init_sel_class,
2520                 .get_best_gw_node = batadv_iv_gw_get_best_gw_node,
2521                 .is_eligible = batadv_iv_gw_is_eligible,
2522                 .dump = batadv_iv_gw_dump,
2523         },
2524 };
2525
2526 /**
2527  * batadv_iv_init() - B.A.T.M.A.N. IV initialization function
2528  *
2529  * Return: 0 on success or negative error number in case of failure
2530  */
2531 int __init batadv_iv_init(void)
2532 {
2533         int ret;
2534
2535         /* batman originator packet */
2536         ret = batadv_recv_handler_register(BATADV_IV_OGM,
2537                                            batadv_iv_ogm_receive);
2538         if (ret < 0)
2539                 goto out;
2540
2541         ret = batadv_algo_register(&batadv_batman_iv);
2542         if (ret < 0)
2543                 goto handler_unregister;
2544
2545         goto out;
2546
2547 handler_unregister:
2548         batadv_recv_handler_unregister(BATADV_IV_OGM);
2549 out:
2550         return ret;
2551 }