net/batman-adv/bat_iv_ogm.c

   1 /* Copyright (C) 2007-2016  B.A.T.M.A.N. contributors:
   2  *
   3  * Marek Lindner, Simon Wunderlich
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of version 2 of the GNU General Public
   7  * License as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "bat_iv_ogm.h"
  19 #include "main.h"
  20
  21 #include <linux/atomic.h>
  22 #include <linux/bitmap.h>
  23 #include <linux/bitops.h>
  24 #include <linux/bug.h>
  25 #include <linux/byteorder/generic.h>
  26 #include <linux/cache.h>
  27 #include <linux/errno.h>
  28 #include <linux/etherdevice.h>
  29 #include <linux/fs.h>
  30 #include <linux/if_ether.h>
  31 #include <linux/init.h>
  32 #include <linux/jiffies.h>
  33 #include <linux/kernel.h>
  34 #include <linux/kref.h>
  35 #include <linux/list.h>
  36 #include <linux/lockdep.h>
  37 #include <linux/netdevice.h>
  38 #include <linux/pkt_sched.h>
  39 #include <linux/printk.h>
  40 #include <linux/random.h>
  41 #include <linux/rculist.h>
  42 #include <linux/rcupdate.h>
  43 #include <linux/seq_file.h>
  44 #include <linux/skbuff.h>
  45 #include <linux/slab.h>
  46 #include <linux/spinlock.h>
  47 #include <linux/stddef.h>
  48 #include <linux/string.h>
  49 #include <linux/types.h>
  50 #include <linux/workqueue.h>
  51
  52 #include "bat_algo.h"
  53 #include "bitarray.h"
  54 #include "hard-interface.h"
  55 #include "hash.h"
  56 #include "log.h"
  57 #include "network-coding.h"
  58 #include "originator.h"
  59 #include "packet.h"
  60 #include "routing.h"
  61 #include "send.h"
  62 #include "translation-table.h"
  63 #include "tvlv.h"
  64
  65 static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work);
  66
  67 /**
  68  * enum batadv_dup_status - duplicate status
  69  * @BATADV_NO_DUP: the packet is no duplicate
  70  * @BATADV_ORIG_DUP: OGM is a duplicate in the originator (but not for the
  71  *  neighbor)
  72  * @BATADV_NEIGH_DUP: OGM is a duplicate for the neighbor
  73  * @BATADV_PROTECTED: originator is currently protected (after reboot)
  74  */
  75 enum batadv_dup_status {
  76         BATADV_NO_DUP = 0,
  77         BATADV_ORIG_DUP,
  78         BATADV_NEIGH_DUP,
  79         BATADV_PROTECTED,
  80 };
  81
  82 /**
  83  * batadv_ring_buffer_set - update the ring buffer with the given value
  84  * @lq_recv: pointer to the ring buffer
  85  * @lq_index: index to store the value at
  86  * @value: value to store in the ring buffer
  87  */
  88 static void batadv_ring_buffer_set(u8 lq_recv[], u8 *lq_index, u8 value)
  89 {
  90         lq_recv[*lq_index] = value;
  91         *lq_index = (*lq_index + 1) % BATADV_TQ_GLOBAL_WINDOW_SIZE;
  92 }
  93
  94 /**
  95  * batadv_ring_buffer_avg - compute the average of all non-zero values stored
  96  * in the given ring buffer
  97  * @lq_recv: pointer to the ring buffer
  98  *
  99  * Return: computed average value.
 100  */
 101 static u8 batadv_ring_buffer_avg(const u8 lq_recv[])
 102 {
 103         const u8 *ptr;
 104         u16 count = 0;
 105         u16 i = 0;
 106         u16 sum = 0;
 107
 108         ptr = lq_recv;
 109
 110         while (i < BATADV_TQ_GLOBAL_WINDOW_SIZE) {
 111                 if (*ptr != 0) {
 112                         count++;
 113                         sum += *ptr;
 114                 }
 115
 116                 i++;
 117                 ptr++;
 118         }
 119
 120         if (count == 0)
 121                 return 0;
 122
 123         return (u8)(sum / count);
 124 }
 125
 126 /**
 127  * batadv_iv_ogm_orig_free - free the private resources allocated for this
 128  *  orig_node
 129  * @orig_node: the orig_node for which the resources have to be free'd
 130  */
 131 static void batadv_iv_ogm_orig_free(struct batadv_orig_node *orig_node)
 132 {
 133         kfree(orig_node->bat_iv.bcast_own);
 134         kfree(orig_node->bat_iv.bcast_own_sum);
 135 }
 136
 137 /**
 138  * batadv_iv_ogm_orig_add_if - change the private structures of the orig_node to
 139  *  include the new hard-interface
 140  * @orig_node: the orig_node that has to be changed
 141  * @max_if_num: the current amount of interfaces
 142  *
 143  * Return: 0 on success, a negative error code otherwise.
 144  */
 145 static int batadv_iv_ogm_orig_add_if(struct batadv_orig_node *orig_node,
 146                                      int max_if_num)
 147 {
 148         void *data_ptr;
 149         size_t old_size;
 150         int ret = -ENOMEM;
 151
 152         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 153
 154         old_size = (max_if_num - 1) * sizeof(unsigned long) * BATADV_NUM_WORDS;
 155         data_ptr = kmalloc_array(max_if_num,
 156                                  BATADV_NUM_WORDS * sizeof(unsigned long),
 157                                  GFP_ATOMIC);
 158         if (!data_ptr)
 159                 goto unlock;
 160
 161         memcpy(data_ptr, orig_node->bat_iv.bcast_own, old_size);
 162         kfree(orig_node->bat_iv.bcast_own);
 163         orig_node->bat_iv.bcast_own = data_ptr;
 164
 165         data_ptr = kmalloc_array(max_if_num, sizeof(u8), GFP_ATOMIC);
 166         if (!data_ptr)
 167                 goto unlock;
 168
 169         memcpy(data_ptr, orig_node->bat_iv.bcast_own_sum,
 170                (max_if_num - 1) * sizeof(u8));
 171         kfree(orig_node->bat_iv.bcast_own_sum);
 172         orig_node->bat_iv.bcast_own_sum = data_ptr;
 173
 174         ret = 0;
 175
 176 unlock:
 177         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 178
 179         return ret;
 180 }
 181
 182 /**
 183  * batadv_iv_ogm_drop_bcast_own_entry - drop section of bcast_own
 184  * @orig_node: the orig_node that has to be changed
 185  * @max_if_num: the current amount of interfaces
 186  * @del_if_num: the index of the interface being removed
 187  */
 188 static void
 189 batadv_iv_ogm_drop_bcast_own_entry(struct batadv_orig_node *orig_node,
 190                                    int max_if_num, int del_if_num)
 191 {
 192         size_t chunk_size;
 193         size_t if_offset;
 194         void *data_ptr;
 195
 196         lockdep_assert_held(&orig_node->bat_iv.ogm_cnt_lock);
 197
 198         chunk_size = sizeof(unsigned long) * BATADV_NUM_WORDS;
 199         data_ptr = kmalloc_array(max_if_num, chunk_size, GFP_ATOMIC);
 200         if (!data_ptr)
 201                 /* use old buffer when new one could not be allocated */
 202                 data_ptr = orig_node->bat_iv.bcast_own;
 203
 204         /* copy first part */
 205         memmove(data_ptr, orig_node->bat_iv.bcast_own, del_if_num * chunk_size);
 206
 207         /* copy second part */
 208         if_offset = (del_if_num + 1) * chunk_size;
 209         memmove((char *)data_ptr + del_if_num * chunk_size,
 210                 (uint8_t *)orig_node->bat_iv.bcast_own + if_offset,
 211                 (max_if_num - del_if_num) * chunk_size);
 212
 213         /* bcast_own was shrunk down in new buffer; free old one */
 214         if (orig_node->bat_iv.bcast_own != data_ptr) {
 215                 kfree(orig_node->bat_iv.bcast_own);
 216                 orig_node->bat_iv.bcast_own = data_ptr;
 217         }
 218 }
 219
 220 /**
 221  * batadv_iv_ogm_drop_bcast_own_sum_entry - drop section of bcast_own_sum
 222  * @orig_node: the orig_node that has to be changed
 223  * @max_if_num: the current amount of interfaces
 224  * @del_if_num: the index of the interface being removed
 225  */
 226 static void
 227 batadv_iv_ogm_drop_bcast_own_sum_entry(struct batadv_orig_node *orig_node,
 228                                        int max_if_num, int del_if_num)
 229 {
 230         size_t if_offset;
 231         void *data_ptr;
 232
 233         lockdep_assert_held(&orig_node->bat_iv.ogm_cnt_lock);
 234
 235         data_ptr = kmalloc_array(max_if_num, sizeof(u8), GFP_ATOMIC);
 236         if (!data_ptr)
 237                 /* use old buffer when new one could not be allocated */
 238                 data_ptr = orig_node->bat_iv.bcast_own_sum;
 239
 240         memmove(data_ptr, orig_node->bat_iv.bcast_own_sum,
 241                 del_if_num * sizeof(u8));
 242
 243         if_offset = (del_if_num + 1) * sizeof(u8);
 244         memmove((char *)data_ptr + del_if_num * sizeof(u8),
 245                 orig_node->bat_iv.bcast_own_sum + if_offset,
 246                 (max_if_num - del_if_num) * sizeof(u8));
 247
 248         /* bcast_own_sum was shrunk down in new buffer; free old one */
 249         if (orig_node->bat_iv.bcast_own_sum != data_ptr) {
 250                 kfree(orig_node->bat_iv.bcast_own_sum);
 251                 orig_node->bat_iv.bcast_own_sum = data_ptr;
 252         }
 253 }
 254
 255 /**
 256  * batadv_iv_ogm_orig_del_if - change the private structures of the orig_node to
 257  *  exclude the removed interface
 258  * @orig_node: the orig_node that has to be changed
 259  * @max_if_num: the current amount of interfaces
 260  * @del_if_num: the index of the interface being removed
 261  *
 262  * Return: 0 on success, a negative error code otherwise.
 263  */
 264 static int batadv_iv_ogm_orig_del_if(struct batadv_orig_node *orig_node,
 265                                      int max_if_num, int del_if_num)
 266 {
 267         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 268
 269         if (max_if_num == 0) {
 270                 kfree(orig_node->bat_iv.bcast_own);
 271                 kfree(orig_node->bat_iv.bcast_own_sum);
 272                 orig_node->bat_iv.bcast_own = NULL;
 273                 orig_node->bat_iv.bcast_own_sum = NULL;
 274         } else {
 275                 batadv_iv_ogm_drop_bcast_own_entry(orig_node, max_if_num,
 276                                                    del_if_num);
 277                 batadv_iv_ogm_drop_bcast_own_sum_entry(orig_node, max_if_num,
 278                                                        del_if_num);
 279         }
 280
 281         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 282
 283         return 0;
 284 }
 285
 286 /**
 287  * batadv_iv_ogm_orig_get - retrieve or create (if does not exist) an originator
 288  * @bat_priv: the bat priv with all the soft interface information
 289  * @addr: mac address of the originator
 290  *
 291  * Return: the originator object corresponding to the passed mac address or NULL
 292  * on failure.
 293  * If the object does not exists it is created an initialised.
 294  */
 295 static struct batadv_orig_node *
 296 batadv_iv_ogm_orig_get(struct batadv_priv *bat_priv, const u8 *addr)
 297 {
 298         struct batadv_orig_node *orig_node;
 299         int size, hash_added;
 300
 301         orig_node = batadv_orig_hash_find(bat_priv, addr);
 302         if (orig_node)
 303                 return orig_node;
 304
 305         orig_node = batadv_orig_node_new(bat_priv, addr);
 306         if (!orig_node)
 307                 return NULL;
 308
 309         spin_lock_init(&orig_node->bat_iv.ogm_cnt_lock);
 310
 311         size = bat_priv->num_ifaces * sizeof(unsigned long) * BATADV_NUM_WORDS;
 312         orig_node->bat_iv.bcast_own = kzalloc(size, GFP_ATOMIC);
 313         if (!orig_node->bat_iv.bcast_own)
 314                 goto free_orig_node;
 315
 316         size = bat_priv->num_ifaces * sizeof(u8);
 317         orig_node->bat_iv.bcast_own_sum = kzalloc(size, GFP_ATOMIC);
 318         if (!orig_node->bat_iv.bcast_own_sum)
 319                 goto free_orig_node;
 320
 321         hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig,
 322                                      batadv_choose_orig, orig_node,
 323                                      &orig_node->hash_entry);
 324         if (hash_added != 0)
 325                 goto free_orig_node;
 326
 327         return orig_node;
 328
 329 free_orig_node:
 330         /* free twice, as batadv_orig_node_new sets refcount to 2 */
 331         batadv_orig_node_put(orig_node);
 332         batadv_orig_node_put(orig_node);
 333
 334         return NULL;
 335 }
 336
 337 static struct batadv_neigh_node *
 338 batadv_iv_ogm_neigh_new(struct batadv_hard_iface *hard_iface,
 339                         const u8 *neigh_addr,
 340                         struct batadv_orig_node *orig_node,
 341                         struct batadv_orig_node *orig_neigh)
 342 {
 343         struct batadv_neigh_node *neigh_node;
 344
 345         neigh_node = batadv_neigh_node_get_or_create(orig_node,
 346                                                      hard_iface, neigh_addr);
 347         if (!neigh_node)
 348                 goto out;
 349
 350         neigh_node->orig_node = orig_neigh;
 351
 352 out:
 353         return neigh_node;
 354 }
 355
 356 static int batadv_iv_ogm_iface_enable(struct batadv_hard_iface *hard_iface)
 357 {
 358         struct batadv_ogm_packet *batadv_ogm_packet;
 359         unsigned char *ogm_buff;
 360         u32 random_seqno;
 361
 362         /* randomize initial seqno to avoid collision */
 363         get_random_bytes(&random_seqno, sizeof(random_seqno));
 364         atomic_set(&hard_iface->bat_iv.ogm_seqno, random_seqno);
 365
 366         hard_iface->bat_iv.ogm_buff_len = BATADV_OGM_HLEN;
 367         ogm_buff = kmalloc(hard_iface->bat_iv.ogm_buff_len, GFP_ATOMIC);
 368         if (!ogm_buff)
 369                 return -ENOMEM;
 370
 371         hard_iface->bat_iv.ogm_buff = ogm_buff;
 372
 373         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 374         batadv_ogm_packet->packet_type = BATADV_IV_OGM;
 375         batadv_ogm_packet->version = BATADV_COMPAT_VERSION;
 376         batadv_ogm_packet->ttl = 2;
 377         batadv_ogm_packet->flags = BATADV_NO_FLAGS;
 378         batadv_ogm_packet->reserved = 0;
 379         batadv_ogm_packet->tq = BATADV_TQ_MAX_VALUE;
 380
 381         return 0;
 382 }
 383
 384 static void batadv_iv_ogm_iface_disable(struct batadv_hard_iface *hard_iface)
 385 {
 386         kfree(hard_iface->bat_iv.ogm_buff);
 387         hard_iface->bat_iv.ogm_buff = NULL;
 388 }
 389
 390 static void batadv_iv_ogm_iface_update_mac(struct batadv_hard_iface *hard_iface)
 391 {
 392         struct batadv_ogm_packet *batadv_ogm_packet;
 393         unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
 394
 395         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 396         ether_addr_copy(batadv_ogm_packet->orig,
 397                         hard_iface->net_dev->dev_addr);
 398         ether_addr_copy(batadv_ogm_packet->prev_sender,
 399                         hard_iface->net_dev->dev_addr);
 400 }
 401
 402 static void
 403 batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface)
 404 {
 405         struct batadv_ogm_packet *batadv_ogm_packet;
 406         unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
 407
 408         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 409         batadv_ogm_packet->ttl = BATADV_TTL;
 410 }
 411
 412 /* when do we schedule our own ogm to be sent */
 413 static unsigned long
 414 batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
 415 {
 416         unsigned int msecs;
 417
 418         msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
 419         msecs += prandom_u32() % (2 * BATADV_JITTER);
 420
 421         return jiffies + msecs_to_jiffies(msecs);
 422 }
 423
 424 /* when do we schedule a ogm packet to be sent */
 425 static unsigned long batadv_iv_ogm_fwd_send_time(void)
 426 {
 427         return jiffies + msecs_to_jiffies(prandom_u32() % (BATADV_JITTER / 2));
 428 }
 429
 430 /* apply hop penalty for a normal link */
 431 static u8 batadv_hop_penalty(u8 tq, const struct batadv_priv *bat_priv)
 432 {
 433         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
 434         int new_tq;
 435
 436         new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty);
 437         new_tq /= BATADV_TQ_MAX_VALUE;
 438
 439         return new_tq;
 440 }
 441
 442 /**
 443  * batadv_iv_ogm_aggr_packet - checks if there is another OGM attached
 444  * @buff_pos: current position in the skb
 445  * @packet_len: total length of the skb
 446  * @tvlv_len: tvlv length of the previously considered OGM
 447  *
 448  * Return: true if there is enough space for another OGM, false otherwise.
 449  */
 450 static bool batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
 451                                       __be16 tvlv_len)
 452 {
 453         int next_buff_pos = 0;
 454
 455         next_buff_pos += buff_pos + BATADV_OGM_HLEN;
 456         next_buff_pos += ntohs(tvlv_len);
 457
 458         return (next_buff_pos <= packet_len) &&
 459                (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
 460 }
 461
 462 /* send a batman ogm to a given interface */
 463 static void batadv_iv_ogm_send_to_if(struct batadv_forw_packet *forw_packet,
 464                                      struct batadv_hard_iface *hard_iface)
 465 {
 466         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 467         const char *fwd_str;
 468         u8 packet_num;
 469         s16 buff_pos;
 470         struct batadv_ogm_packet *batadv_ogm_packet;
 471         struct sk_buff *skb;
 472         u8 *packet_pos;
 473
 474         if (hard_iface->if_status != BATADV_IF_ACTIVE)
 475                 return;
 476
 477         packet_num = 0;
 478         buff_pos = 0;
 479         packet_pos = forw_packet->skb->data;
 480         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 481
 482         /* adjust all flags and log packets */
 483         while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
 484                                          batadv_ogm_packet->tvlv_len)) {
 485                 /* we might have aggregated direct link packets with an
 486                  * ordinary base packet
 487                  */
 488                 if (forw_packet->direct_link_flags & BIT(packet_num) &&
 489                     forw_packet->if_incoming == hard_iface)
 490                         batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 491                 else
 492                         batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 493
 494                 if (packet_num > 0 || !forw_packet->own)
 495                         fwd_str = "Forwarding";
 496                 else
 497                         fwd_str = "Sending own";
 498
 499                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 500                            "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s) on interface %s [%pM]\n",
 501                            fwd_str, (packet_num > 0 ? "aggregated " : ""),
 502                            batadv_ogm_packet->orig,
 503                            ntohl(batadv_ogm_packet->seqno),
 504                            batadv_ogm_packet->tq, batadv_ogm_packet->ttl,
 505                            ((batadv_ogm_packet->flags & BATADV_DIRECTLINK) ?
 506                             "on" : "off"),
 507                            hard_iface->net_dev->name,
 508                            hard_iface->net_dev->dev_addr);
 509
 510                 buff_pos += BATADV_OGM_HLEN;
 511                 buff_pos += ntohs(batadv_ogm_packet->tvlv_len);
 512                 packet_num++;
 513                 packet_pos = forw_packet->skb->data + buff_pos;
 514                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 515         }
 516
 517         /* create clone because function is called more than once */
 518         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
 519         if (skb) {
 520                 batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
 521                 batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
 522                                    skb->len + ETH_HLEN);
 523                 batadv_send_broadcast_skb(skb, hard_iface);
 524         }
 525 }
 526
 527 /* send a batman ogm packet */
 528 static void batadv_iv_ogm_emit(struct batadv_forw_packet *forw_packet)
 529 {
 530         struct net_device *soft_iface;
 531         struct batadv_priv *bat_priv;
 532         struct batadv_hard_iface *primary_if = NULL;
 533
 534         if (!forw_packet->if_incoming) {
 535                 pr_err("Error - can't forward packet: incoming iface not specified\n");
 536                 goto out;
 537         }
 538
 539         soft_iface = forw_packet->if_incoming->soft_iface;
 540         bat_priv = netdev_priv(soft_iface);
 541
 542         if (WARN_ON(!forw_packet->if_outgoing))
 543                 goto out;
 544
 545         if (WARN_ON(forw_packet->if_outgoing->soft_iface != soft_iface))
 546                 goto out;
 547
 548         if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE)
 549                 goto out;
 550
 551         primary_if = batadv_primary_if_get_selected(bat_priv);
 552         if (!primary_if)
 553                 goto out;
 554
 555         /* only for one specific outgoing interface */
 556         batadv_iv_ogm_send_to_if(forw_packet, forw_packet->if_outgoing);
 557
 558 out:
 559         if (primary_if)
 560                 batadv_hardif_put(primary_if);
 561 }
 562
 563 /**
 564  * batadv_iv_ogm_can_aggregate - find out if an OGM can be aggregated on an
 565  *  existing forward packet
 566  * @new_bat_ogm_packet: OGM packet to be aggregated
 567  * @bat_priv: the bat priv with all the soft interface information
 568  * @packet_len: (total) length of the OGM
 569  * @send_time: timestamp (jiffies) when the packet is to be sent
 570  * @directlink: true if this is a direct link packet
 571  * @if_incoming: interface where the packet was received
 572  * @if_outgoing: interface for which the retransmission should be considered
 573  * @forw_packet: the forwarded packet which should be checked
 574  *
 575  * Return: true if new_packet can be aggregated with forw_packet
 576  */
 577 static bool
 578 batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet,
 579                             struct batadv_priv *bat_priv,
 580                             int packet_len, unsigned long send_time,
 581                             bool directlink,
 582                             const struct batadv_hard_iface *if_incoming,
 583                             const struct batadv_hard_iface *if_outgoing,
 584                             const struct batadv_forw_packet *forw_packet)
 585 {
 586         struct batadv_ogm_packet *batadv_ogm_packet;
 587         int aggregated_bytes = forw_packet->packet_len + packet_len;
 588         struct batadv_hard_iface *primary_if = NULL;
 589         bool res = false;
 590         unsigned long aggregation_end_time;
 591
 592         batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
 593         aggregation_end_time = send_time;
 594         aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 595
 596         /* we can aggregate the current packet to this aggregated packet
 597          * if:
 598          *
 599          * - the send time is within our MAX_AGGREGATION_MS time
 600          * - the resulting packet wont be bigger than
 601          *   MAX_AGGREGATION_BYTES
 602          * otherwise aggregation is not possible
 603          */
 604         if (!time_before(send_time, forw_packet->send_time) ||
 605             !time_after_eq(aggregation_end_time, forw_packet->send_time))
 606                 return false;
 607
 608         if (aggregated_bytes > BATADV_MAX_AGGREGATION_BYTES)
 609                 return false;
 610
 611         /* packet is not leaving on the same interface. */
 612         if (forw_packet->if_outgoing != if_outgoing)
 613                 return false;
 614
 615         /* check aggregation compatibility
 616          * -> direct link packets are broadcasted on
 617          *    their interface only
 618          * -> aggregate packet if the current packet is
 619          *    a "global" packet as well as the base
 620          *    packet
 621          */
 622         primary_if = batadv_primary_if_get_selected(bat_priv);
 623         if (!primary_if)
 624                 return false;
 625
 626         /* packets without direct link flag and high TTL
 627          * are flooded through the net
 628          */
 629         if (!directlink &&
 630             !(batadv_ogm_packet->flags & BATADV_DIRECTLINK) &&
 631             batadv_ogm_packet->ttl != 1 &&
 632
 633             /* own packets originating non-primary
 634              * interfaces leave only that interface
 635              */
 636             (!forw_packet->own ||
 637              forw_packet->if_incoming == primary_if)) {
 638                 res = true;
 639                 goto out;
 640         }
 641
 642         /* if the incoming packet is sent via this one
 643          * interface only - we still can aggregate
 644          */
 645         if (directlink &&
 646             new_bat_ogm_packet->ttl == 1 &&
 647             forw_packet->if_incoming == if_incoming &&
 648
 649             /* packets from direct neighbors or
 650              * own secondary interface packets
 651              * (= secondary interface packets in general)
 652              */
 653             (batadv_ogm_packet->flags & BATADV_DIRECTLINK ||
 654              (forw_packet->own &&
 655               forw_packet->if_incoming != primary_if))) {
 656                 res = true;
 657                 goto out;
 658         }
 659
 660 out:
 661         if (primary_if)
 662                 batadv_hardif_put(primary_if);
 663         return res;
 664 }
 665
 666 /**
 667  * batadv_iv_ogm_aggregate_new - create a new aggregated packet and add this
 668  *  packet to it.
 669  * @packet_buff: pointer to the OGM
 670  * @packet_len: (total) length of the OGM
 671  * @send_time: timestamp (jiffies) when the packet is to be sent
 672  * @direct_link: whether this OGM has direct link status
 673  * @if_incoming: interface where the packet was received
 674  * @if_outgoing: interface for which the retransmission should be considered
 675  * @own_packet: true if it is a self-generated ogm
 676  */
 677 static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 678                                         int packet_len, unsigned long send_time,
 679                                         bool direct_link,
 680                                         struct batadv_hard_iface *if_incoming,
 681                                         struct batadv_hard_iface *if_outgoing,
 682                                         int own_packet)
 683 {
 684         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 685         struct batadv_forw_packet *forw_packet_aggr;
 686         unsigned char *skb_buff;
 687         unsigned int skb_size;
 688
 689         /* own packet should always be scheduled */
 690         if (!own_packet) {
 691                 if (!batadv_atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
 692                         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 693                                    "batman packet queue full\n");
 694                         return;
 695                 }
 696         }
 697
 698         forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
 699         if (!forw_packet_aggr)
 700                 goto out_nomem;
 701
 702         if (atomic_read(&bat_priv->aggregated_ogms) &&
 703             packet_len < BATADV_MAX_AGGREGATION_BYTES)
 704                 skb_size = BATADV_MAX_AGGREGATION_BYTES;
 705         else
 706                 skb_size = packet_len;
 707
 708         skb_size += ETH_HLEN;
 709
 710         forw_packet_aggr->skb = netdev_alloc_skb_ip_align(NULL, skb_size);
 711         if (!forw_packet_aggr->skb)
 712                 goto out_free_forw_packet;
 713         forw_packet_aggr->skb->priority = TC_PRIO_CONTROL;
 714         skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
 715
 716         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 717         forw_packet_aggr->packet_len = packet_len;
 718         memcpy(skb_buff, packet_buff, packet_len);
 719
 720         kref_get(&if_incoming->refcount);
 721         kref_get(&if_outgoing->refcount);
 722         forw_packet_aggr->own = own_packet;
 723         forw_packet_aggr->if_incoming = if_incoming;
 724         forw_packet_aggr->if_outgoing = if_outgoing;
 725         forw_packet_aggr->num_packets = 0;
 726         forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
 727         forw_packet_aggr->send_time = send_time;
 728
 729         /* save packet direct link flag status */
 730         if (direct_link)
 731                 forw_packet_aggr->direct_link_flags |= 1;
 732
 733         /* add new packet to packet list */
 734         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 735         hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
 736         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 737
 738         /* start timer for this packet */
 739         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 740                           batadv_iv_send_outstanding_bat_ogm_packet);
 741         queue_delayed_work(batadv_event_workqueue,
 742                            &forw_packet_aggr->delayed_work,
 743                            send_time - jiffies);
 744
 745         return;
 746 out_free_forw_packet:
 747         kfree(forw_packet_aggr);
 748 out_nomem:
 749         if (!own_packet)
 750                 atomic_inc(&bat_priv->batman_queue_left);
 751 }
 752
 753 /* aggregate a new packet into the existing ogm packet */
 754 static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr,
 755                                     const unsigned char *packet_buff,
 756                                     int packet_len, bool direct_link)
 757 {
 758         unsigned char *skb_buff;
 759         unsigned long new_direct_link_flag;
 760
 761         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 762         memcpy(skb_buff, packet_buff, packet_len);
 763         forw_packet_aggr->packet_len += packet_len;
 764         forw_packet_aggr->num_packets++;
 765
 766         /* save packet direct link flag status */
 767         if (direct_link) {
 768                 new_direct_link_flag = BIT(forw_packet_aggr->num_packets);
 769                 forw_packet_aggr->direct_link_flags |= new_direct_link_flag;
 770         }
 771 }
 772
 773 /**
 774  * batadv_iv_ogm_queue_add - queue up an OGM for transmission
 775  * @bat_priv: the bat priv with all the soft interface information
 776  * @packet_buff: pointer to the OGM
 777  * @packet_len: (total) length of the OGM
 778  * @if_incoming: interface where the packet was received
 779  * @if_outgoing: interface for which the retransmission should be considered
 780  * @own_packet: true if it is a self-generated ogm
 781  * @send_time: timestamp (jiffies) when the packet is to be sent
 782  */
 783 static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv,
 784                                     unsigned char *packet_buff,
 785                                     int packet_len,
 786                                     struct batadv_hard_iface *if_incoming,
 787                                     struct batadv_hard_iface *if_outgoing,
 788                                     int own_packet, unsigned long send_time)
 789 {
 790         /* _aggr -> pointer to the packet we want to aggregate with
 791          * _pos -> pointer to the position in the queue
 792          */
 793         struct batadv_forw_packet *forw_packet_aggr = NULL;
 794         struct batadv_forw_packet *forw_packet_pos = NULL;
 795         struct batadv_ogm_packet *batadv_ogm_packet;
 796         bool direct_link;
 797         unsigned long max_aggregation_jiffies;
 798
 799         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
 800         direct_link = !!(batadv_ogm_packet->flags & BATADV_DIRECTLINK);
 801         max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 802
 803         /* find position for the packet in the forward queue */
 804         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 805         /* own packets are not to be aggregated */
 806         if (atomic_read(&bat_priv->aggregated_ogms) && !own_packet) {
 807                 hlist_for_each_entry(forw_packet_pos,
 808                                      &bat_priv->forw_bat_list, list) {
 809                         if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet,
 810                                                         bat_priv, packet_len,
 811                                                         send_time, direct_link,
 812                                                         if_incoming,
 813                                                         if_outgoing,
 814                                                         forw_packet_pos)) {
 815                                 forw_packet_aggr = forw_packet_pos;
 816                                 break;
 817                         }
 818                 }
 819         }
 820
 821         /* nothing to aggregate with - either aggregation disabled or no
 822          * suitable aggregation packet found
 823          */
 824         if (!forw_packet_aggr) {
 825                 /* the following section can run without the lock */
 826                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 827
 828                 /* if we could not aggregate this packet with one of the others
 829                  * we hold it back for a while, so that it might be aggregated
 830                  * later on
 831                  */
 832                 if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
 833                         send_time += max_aggregation_jiffies;
 834
 835                 batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
 836                                             send_time, direct_link,
 837                                             if_incoming, if_outgoing,
 838                                             own_packet);
 839         } else {
 840                 batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 841                                         packet_len, direct_link);
 842                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 843         }
 844 }
 845
 846 static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
 847                                   const struct ethhdr *ethhdr,
 848                                   struct batadv_ogm_packet *batadv_ogm_packet,
 849                                   bool is_single_hop_neigh,
 850                                   bool is_from_best_next_hop,
 851                                   struct batadv_hard_iface *if_incoming,
 852                                   struct batadv_hard_iface *if_outgoing)
 853 {
 854         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 855         u16 tvlv_len;
 856
 857         if (batadv_ogm_packet->ttl <= 1) {
 858                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
 859                 return;
 860         }
 861
 862         if (!is_from_best_next_hop) {
 863                 /* Mark the forwarded packet when it is not coming from our
 864                  * best next hop. We still need to forward the packet for our
 865                  * neighbor link quality detection to work in case the packet
 866                  * originated from a single hop neighbor. Otherwise we can
 867                  * simply drop the ogm.
 868                  */
 869                 if (is_single_hop_neigh)
 870                         batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP;
 871                 else
 872                         return;
 873         }
 874
 875         tvlv_len = ntohs(batadv_ogm_packet->tvlv_len);
 876
 877         batadv_ogm_packet->ttl--;
 878         ether_addr_copy(batadv_ogm_packet->prev_sender, ethhdr->h_source);
 879
 880         /* apply hop penalty */
 881         batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq,
 882                                                    bat_priv);
 883
 884         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 885                    "Forwarding packet: tq: %i, ttl: %i\n",
 886                    batadv_ogm_packet->tq, batadv_ogm_packet->ttl);
 887
 888         if (is_single_hop_neigh)
 889                 batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 890         else
 891                 batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 892
 893         batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
 894                                 BATADV_OGM_HLEN + tvlv_len,
 895                                 if_incoming, if_outgoing, 0,
 896                                 batadv_iv_ogm_fwd_send_time());
 897 }
 898
 899 /**
 900  * batadv_iv_ogm_slide_own_bcast_window - bitshift own OGM broadcast windows for
 901  * the given interface
 902  * @hard_iface: the interface for which the windows have to be shifted
 903  */
 904 static void
 905 batadv_iv_ogm_slide_own_bcast_window(struct batadv_hard_iface *hard_iface)
 906 {
 907         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 908         struct batadv_hashtable *hash = bat_priv->orig_hash;
 909         struct hlist_head *head;
 910         struct batadv_orig_node *orig_node;
 911         unsigned long *word;
 912         u32 i;
 913         size_t word_index;
 914         u8 *w;
 915         int if_num;
 916
 917         for (i = 0; i < hash->size; i++) {
 918                 head = &hash->table[i];
 919
 920                 rcu_read_lock();
 921                 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
 922                         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 923                         word_index = hard_iface->if_num * BATADV_NUM_WORDS;
 924                         word = &orig_node->bat_iv.bcast_own[word_index];
 925
 926                         batadv_bit_get_packet(bat_priv, word, 1, 0);
 927                         if_num = hard_iface->if_num;
 928                         w = &orig_node->bat_iv.bcast_own_sum[if_num];
 929                         *w = bitmap_weight(word, BATADV_TQ_LOCAL_WINDOW_SIZE);
 930                         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
 931                 }
 932                 rcu_read_unlock();
 933         }
 934 }
 935
 936 static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
 937 {
 938         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 939         unsigned char **ogm_buff = &hard_iface->bat_iv.ogm_buff;
 940         struct batadv_ogm_packet *batadv_ogm_packet;
 941         struct batadv_hard_iface *primary_if, *tmp_hard_iface;
 942         int *ogm_buff_len = &hard_iface->bat_iv.ogm_buff_len;
 943         u32 seqno;
 944         u16 tvlv_len = 0;
 945         unsigned long send_time;
 946
 947         if ((hard_iface->if_status == BATADV_IF_NOT_IN_USE) ||
 948             (hard_iface->if_status == BATADV_IF_TO_BE_REMOVED))
 949                 return;
 950
 951         /* the interface gets activated here to avoid race conditions between
 952          * the moment of activating the interface in
 953          * hardif_activate_interface() where the originator mac is set and
 954          * outdated packets (especially uninitialized mac addresses) in the
 955          * packet queue
 956          */
 957         if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED)
 958                 hard_iface->if_status = BATADV_IF_ACTIVE;
 959
 960         primary_if = batadv_primary_if_get_selected(bat_priv);
 961
 962         if (hard_iface == primary_if) {
 963                 /* tt changes have to be committed before the tvlv data is
 964                  * appended as it may alter the tt tvlv container
 965                  */
 966                 batadv_tt_local_commit_changes(bat_priv);
 967                 tvlv_len = batadv_tvlv_container_ogm_append(bat_priv, ogm_buff,
 968                                                             ogm_buff_len,
 969                                                             BATADV_OGM_HLEN);
 970         }
 971
 972         batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff);
 973         batadv_ogm_packet->tvlv_len = htons(tvlv_len);
 974
 975         /* change sequence number to network order */
 976         seqno = (u32)atomic_read(&hard_iface->bat_iv.ogm_seqno);
 977         batadv_ogm_packet->seqno = htonl(seqno);
 978         atomic_inc(&hard_iface->bat_iv.ogm_seqno);
 979
 980         batadv_iv_ogm_slide_own_bcast_window(hard_iface);
 981
 982         send_time = batadv_iv_ogm_emit_send_time(bat_priv);
 983
 984         if (hard_iface != primary_if) {
 985                 /* OGMs from secondary interfaces are only scheduled on their
 986                  * respective interfaces.
 987                  */
 988                 batadv_iv_ogm_queue_add(bat_priv, *ogm_buff, *ogm_buff_len,
 989                                         hard_iface, hard_iface, 1, send_time);
 990                 goto out;
 991         }
 992
 993         /* OGMs from primary interfaces are scheduled on all
 994          * interfaces.
 995          */
 996         rcu_read_lock();
 997         list_for_each_entry_rcu(tmp_hard_iface, &batadv_hardif_list, list) {
 998                 if (tmp_hard_iface->soft_iface != hard_iface->soft_iface)
 999                         continue;
1000
1001                 if (!kref_get_unless_zero(&tmp_hard_iface->refcount))
1002                         continue;
1003
1004                 batadv_iv_ogm_queue_add(bat_priv, *ogm_buff,
1005                                         *ogm_buff_len, hard_iface,
1006                                         tmp_hard_iface, 1, send_time);
1007
1008                 batadv_hardif_put(tmp_hard_iface);
1009         }
1010         rcu_read_unlock();
1011
1012 out:
1013         if (primary_if)
1014                 batadv_hardif_put(primary_if);
1015 }
1016
1017 /**
1018  * batadv_iv_ogm_orig_update - use OGM to update corresponding data in an
1019  *  originator
1020  * @bat_priv: the bat priv with all the soft interface information
1021  * @orig_node: the orig node who originally emitted the ogm packet
1022  * @orig_ifinfo: ifinfo for the outgoing interface of the orig_node
1023  * @ethhdr: Ethernet header of the OGM
1024  * @batadv_ogm_packet: the ogm packet
1025  * @if_incoming: interface where the packet was received
1026  * @if_outgoing: interface for which the retransmission should be considered
1027  * @dup_status: the duplicate status of this ogm packet.
1028  */
1029 static void
1030 batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv,
1031                           struct batadv_orig_node *orig_node,
1032                           struct batadv_orig_ifinfo *orig_ifinfo,
1033                           const struct ethhdr *ethhdr,
1034                           const struct batadv_ogm_packet *batadv_ogm_packet,
1035                           struct batadv_hard_iface *if_incoming,
1036                           struct batadv_hard_iface *if_outgoing,
1037                           enum batadv_dup_status dup_status)
1038 {
1039         struct batadv_neigh_ifinfo *neigh_ifinfo = NULL;
1040         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
1041         struct batadv_neigh_node *neigh_node = NULL;
1042         struct batadv_neigh_node *tmp_neigh_node = NULL;
1043         struct batadv_neigh_node *router = NULL;
1044         struct batadv_orig_node *orig_node_tmp;
1045         int if_num;
1046         u8 sum_orig, sum_neigh;
1047         u8 *neigh_addr;
1048         u8 tq_avg;
1049
1050         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1051                    "update_originator(): Searching and updating originator entry of received packet\n");
1052
1053         rcu_read_lock();
1054         hlist_for_each_entry_rcu(tmp_neigh_node,
1055                                  &orig_node->neigh_list, list) {
1056                 neigh_addr = tmp_neigh_node->addr;
1057                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
1058                     tmp_neigh_node->if_incoming == if_incoming &&
1059                     kref_get_unless_zero(&tmp_neigh_node->refcount)) {
1060                         if (WARN(neigh_node, "too many matching neigh_nodes"))
1061                                 batadv_neigh_node_put(neigh_node);
1062                         neigh_node = tmp_neigh_node;
1063                         continue;
1064                 }
1065
1066                 if (dup_status != BATADV_NO_DUP)
1067                         continue;
1068
1069                 /* only update the entry for this outgoing interface */
1070                 neigh_ifinfo = batadv_neigh_ifinfo_get(tmp_neigh_node,
1071                                                        if_outgoing);
1072                 if (!neigh_ifinfo)
1073                         continue;
1074
1075                 spin_lock_bh(&tmp_neigh_node->ifinfo_lock);
1076                 batadv_ring_buffer_set(neigh_ifinfo->bat_iv.tq_recv,
1077                                        &neigh_ifinfo->bat_iv.tq_index, 0);
1078                 tq_avg = batadv_ring_buffer_avg(neigh_ifinfo->bat_iv.tq_recv);
1079                 neigh_ifinfo->bat_iv.tq_avg = tq_avg;
1080                 spin_unlock_bh(&tmp_neigh_node->ifinfo_lock);
1081
1082                 batadv_neigh_ifinfo_put(neigh_ifinfo);
1083                 neigh_ifinfo = NULL;
1084         }
1085
1086         if (!neigh_node) {
1087                 struct batadv_orig_node *orig_tmp;
1088
1089                 orig_tmp = batadv_iv_ogm_orig_get(bat_priv, ethhdr->h_source);
1090                 if (!orig_tmp)
1091                         goto unlock;
1092
1093                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
1094                                                      ethhdr->h_source,
1095                                                      orig_node, orig_tmp);
1096
1097                 batadv_orig_node_put(orig_tmp);
1098                 if (!neigh_node)
1099                         goto unlock;
1100         } else {
1101                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1102                            "Updating existing last-hop neighbor of originator\n");
1103         }
1104
1105         rcu_read_unlock();
1106         neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing);
1107         if (!neigh_ifinfo)
1108                 goto out;
1109
1110         neigh_node->last_seen = jiffies;
1111
1112         spin_lock_bh(&neigh_node->ifinfo_lock);
1113         batadv_ring_buffer_set(neigh_ifinfo->bat_iv.tq_recv,
1114                                &neigh_ifinfo->bat_iv.tq_index,
1115                                batadv_ogm_packet->tq);
1116         tq_avg = batadv_ring_buffer_avg(neigh_ifinfo->bat_iv.tq_recv);
1117         neigh_ifinfo->bat_iv.tq_avg = tq_avg;
1118         spin_unlock_bh(&neigh_node->ifinfo_lock);
1119
1120         if (dup_status == BATADV_NO_DUP) {
1121                 orig_ifinfo->last_ttl = batadv_ogm_packet->ttl;
1122                 neigh_ifinfo->last_ttl = batadv_ogm_packet->ttl;
1123         }
1124
1125         /* if this neighbor already is our next hop there is nothing
1126          * to change
1127          */
1128         router = batadv_orig_router_get(orig_node, if_outgoing);
1129         if (router == neigh_node)
1130                 goto out;
1131
1132         if (router) {
1133                 router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing);
1134                 if (!router_ifinfo)
1135                         goto out;
1136
1137                 /* if this neighbor does not offer a better TQ we won't
1138                  * consider it
1139                  */
1140                 if (router_ifinfo->bat_iv.tq_avg > neigh_ifinfo->bat_iv.tq_avg)
1141                         goto out;
1142         }
1143
1144         /* if the TQ is the same and the link not more symmetric we
1145          * won't consider it either
1146          */
1147         if (router_ifinfo &&
1148             neigh_ifinfo->bat_iv.tq_avg == router_ifinfo->bat_iv.tq_avg) {
1149                 orig_node_tmp = router->orig_node;
1150                 spin_lock_bh(&orig_node_tmp->bat_iv.ogm_cnt_lock);
1151                 if_num = router->if_incoming->if_num;
1152                 sum_orig = orig_node_tmp->bat_iv.bcast_own_sum[if_num];
1153                 spin_unlock_bh(&orig_node_tmp->bat_iv.ogm_cnt_lock);
1154
1155                 orig_node_tmp = neigh_node->orig_node;
1156                 spin_lock_bh(&orig_node_tmp->bat_iv.ogm_cnt_lock);
1157                 if_num = neigh_node->if_incoming->if_num;
1158                 sum_neigh = orig_node_tmp->bat_iv.bcast_own_sum[if_num];
1159                 spin_unlock_bh(&orig_node_tmp->bat_iv.ogm_cnt_lock);
1160
1161                 if (sum_orig >= sum_neigh)
1162                         goto out;
1163         }
1164
1165         batadv_update_route(bat_priv, orig_node, if_outgoing, neigh_node);
1166         goto out;
1167
1168 unlock:
1169         rcu_read_unlock();
1170 out:
1171         if (neigh_node)
1172                 batadv_neigh_node_put(neigh_node);
1173         if (router)
1174                 batadv_neigh_node_put(router);
1175         if (neigh_ifinfo)
1176                 batadv_neigh_ifinfo_put(neigh_ifinfo);
1177         if (router_ifinfo)
1178                 batadv_neigh_ifinfo_put(router_ifinfo);
1179 }
1180
1181 /**
1182  * batadv_iv_ogm_calc_tq - calculate tq for current received ogm packet
1183  * @orig_node: the orig node who originally emitted the ogm packet
1184  * @orig_neigh_node: the orig node struct of the neighbor who sent the packet
1185  * @batadv_ogm_packet: the ogm packet
1186  * @if_incoming: interface where the packet was received
1187  * @if_outgoing: interface for which the retransmission should be considered
1188  *
1189  * Return: true if the link can be considered bidirectional, false otherwise
1190  */
1191 static bool batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
1192                                   struct batadv_orig_node *orig_neigh_node,
1193                                   struct batadv_ogm_packet *batadv_ogm_packet,
1194                                   struct batadv_hard_iface *if_incoming,
1195                                   struct batadv_hard_iface *if_outgoing)
1196 {
1197         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1198         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node;
1199         struct batadv_neigh_ifinfo *neigh_ifinfo;
1200         u8 total_count;
1201         u8 orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
1202         unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
1203         int if_num;
1204         unsigned int tq_asym_penalty, inv_asym_penalty;
1205         unsigned int combined_tq;
1206         unsigned int tq_iface_penalty;
1207         bool ret = false;
1208
1209         /* find corresponding one hop neighbor */
1210         rcu_read_lock();
1211         hlist_for_each_entry_rcu(tmp_neigh_node,
1212                                  &orig_neigh_node->neigh_list, list) {
1213                 if (!batadv_compare_eth(tmp_neigh_node->addr,
1214                                         orig_neigh_node->orig))
1215                         continue;
1216
1217                 if (tmp_neigh_node->if_incoming != if_incoming)
1218                         continue;
1219
1220                 if (!kref_get_unless_zero(&tmp_neigh_node->refcount))
1221                         continue;
1222
1223                 neigh_node = tmp_neigh_node;
1224                 break;
1225         }
1226         rcu_read_unlock();
1227
1228         if (!neigh_node)
1229                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
1230                                                      orig_neigh_node->orig,
1231                                                      orig_neigh_node,
1232                                                      orig_neigh_node);
1233
1234         if (!neigh_node)
1235                 goto out;
1236
1237         /* if orig_node is direct neighbor update neigh_node last_seen */
1238         if (orig_node == orig_neigh_node)
1239                 neigh_node->last_seen = jiffies;
1240
1241         orig_node->last_seen = jiffies;
1242
1243         /* find packet count of corresponding one hop neighbor */
1244         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1245         if_num = if_incoming->if_num;
1246         orig_eq_count = orig_neigh_node->bat_iv.bcast_own_sum[if_num];
1247         neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing);
1248         if (neigh_ifinfo) {
1249                 neigh_rq_count = neigh_ifinfo->bat_iv.real_packet_count;
1250                 batadv_neigh_ifinfo_put(neigh_ifinfo);
1251         } else {
1252                 neigh_rq_count = 0;
1253         }
1254         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1255
1256         /* pay attention to not get a value bigger than 100 % */
1257         if (orig_eq_count > neigh_rq_count)
1258                 total_count = neigh_rq_count;
1259         else
1260                 total_count = orig_eq_count;
1261
1262         /* if we have too few packets (too less data) we set tq_own to zero
1263          * if we receive too few packets it is not considered bidirectional
1264          */
1265         if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
1266             neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
1267                 tq_own = 0;
1268         else
1269                 /* neigh_node->real_packet_count is never zero as we
1270                  * only purge old information when getting new
1271                  * information
1272                  */
1273                 tq_own = (BATADV_TQ_MAX_VALUE * total_count) /  neigh_rq_count;
1274
1275         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
1276          * affect the nearly-symmetric links only a little, but
1277          * punishes asymmetric links more.  This will give a value
1278          * between 0 and TQ_MAX_VALUE
1279          */
1280         neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
1281         neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
1282         neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
1283                             BATADV_TQ_LOCAL_WINDOW_SIZE *
1284                             BATADV_TQ_LOCAL_WINDOW_SIZE;
1285         inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
1286         inv_asym_penalty /= neigh_rq_max_cube;
1287         tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;
1288
1289         /* penalize if the OGM is forwarded on the same interface. WiFi
1290          * interfaces and other half duplex devices suffer from throughput
1291          * drops as they can't send and receive at the same time.
1292          */
1293         tq_iface_penalty = BATADV_TQ_MAX_VALUE;
1294         if (if_outgoing && (if_incoming == if_outgoing) &&
1295             batadv_is_wifi_netdev(if_outgoing->net_dev))
1296                 tq_iface_penalty = batadv_hop_penalty(BATADV_TQ_MAX_VALUE,
1297                                                       bat_priv);
1298
1299         combined_tq = batadv_ogm_packet->tq *
1300                       tq_own *
1301                       tq_asym_penalty *
1302                       tq_iface_penalty;
1303         combined_tq /= BATADV_TQ_MAX_VALUE *
1304                        BATADV_TQ_MAX_VALUE *
1305                        BATADV_TQ_MAX_VALUE;
1306         batadv_ogm_packet->tq = combined_tq;
1307
1308         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1309                    "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, iface_penalty: %3i, total tq: %3i, if_incoming = %s, if_outgoing = %s\n",
1310                    orig_node->orig, orig_neigh_node->orig, total_count,
1311                    neigh_rq_count, tq_own, tq_asym_penalty, tq_iface_penalty,
1312                    batadv_ogm_packet->tq, if_incoming->net_dev->name,
1313                    if_outgoing ? if_outgoing->net_dev->name : "DEFAULT");
1314
1315         /* if link has the minimum required transmission quality
1316          * consider it bidirectional
1317          */
1318         if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
1319                 ret = true;
1320
1321 out:
1322         if (neigh_node)
1323                 batadv_neigh_node_put(neigh_node);
1324         return ret;
1325 }
1326
1327 /**
1328  * batadv_iv_ogm_update_seqnos -  process a batman packet for all interfaces,
1329  *  adjust the sequence number and find out whether it is a duplicate
1330  * @ethhdr: ethernet header of the packet
1331  * @batadv_ogm_packet: OGM packet to be considered
1332  * @if_incoming: interface on which the OGM packet was received
1333  * @if_outgoing: interface for which the retransmission should be considered
1334  *
1335  * Return: duplicate status as enum batadv_dup_status
1336  */
1337 static enum batadv_dup_status
1338 batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
1339                             const struct batadv_ogm_packet *batadv_ogm_packet,
1340                             const struct batadv_hard_iface *if_incoming,
1341                             struct batadv_hard_iface *if_outgoing)
1342 {
1343         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1344         struct batadv_orig_node *orig_node;
1345         struct batadv_orig_ifinfo *orig_ifinfo = NULL;
1346         struct batadv_neigh_node *neigh_node;
1347         struct batadv_neigh_ifinfo *neigh_ifinfo;
1348         bool is_dup;
1349         s32 seq_diff;
1350         bool need_update = false;
1351         int set_mark;
1352         enum batadv_dup_status ret = BATADV_NO_DUP;
1353         u32 seqno = ntohl(batadv_ogm_packet->seqno);
1354         u8 *neigh_addr;
1355         u8 packet_count;
1356         unsigned long *bitmap;
1357
1358         orig_node = batadv_iv_ogm_orig_get(bat_priv, batadv_ogm_packet->orig);
1359         if (!orig_node)
1360                 return BATADV_NO_DUP;
1361
1362         orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
1363         if (WARN_ON(!orig_ifinfo)) {
1364                 batadv_orig_node_put(orig_node);
1365                 return 0;
1366         }
1367
1368         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1369         seq_diff = seqno - orig_ifinfo->last_real_seqno;
1370
1371         /* signalize caller that the packet is to be dropped. */
1372         if (!hlist_empty(&orig_node->neigh_list) &&
1373             batadv_window_protected(bat_priv, seq_diff,
1374                                     BATADV_TQ_LOCAL_WINDOW_SIZE,
1375                                     &orig_ifinfo->batman_seqno_reset, NULL)) {
1376                 ret = BATADV_PROTECTED;
1377                 goto out;
1378         }
1379
1380         rcu_read_lock();
1381         hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
1382                 neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node,
1383                                                        if_outgoing);
1384                 if (!neigh_ifinfo)
1385                         continue;
1386
1387                 neigh_addr = neigh_node->addr;
1388                 is_dup = batadv_test_bit(neigh_ifinfo->bat_iv.real_bits,
1389                                          orig_ifinfo->last_real_seqno,
1390                                          seqno);
1391
1392                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
1393                     neigh_node->if_incoming == if_incoming) {
1394                         set_mark = 1;
1395                         if (is_dup)
1396                                 ret = BATADV_NEIGH_DUP;
1397                 } else {
1398                         set_mark = 0;
1399                         if (is_dup && (ret != BATADV_NEIGH_DUP))
1400                                 ret = BATADV_ORIG_DUP;
1401                 }
1402
1403                 /* if the window moved, set the update flag. */
1404                 bitmap = neigh_ifinfo->bat_iv.real_bits;
1405                 need_update |= batadv_bit_get_packet(bat_priv, bitmap,
1406                                                      seq_diff, set_mark);
1407
1408                 packet_count = bitmap_weight(bitmap,
1409                                              BATADV_TQ_LOCAL_WINDOW_SIZE);
1410                 neigh_ifinfo->bat_iv.real_packet_count = packet_count;
1411                 batadv_neigh_ifinfo_put(neigh_ifinfo);
1412         }
1413         rcu_read_unlock();
1414
1415         if (need_update) {
1416                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1417                            "%s updating last_seqno: old %u, new %u\n",
1418                            if_outgoing ? if_outgoing->net_dev->name : "DEFAULT",
1419                            orig_ifinfo->last_real_seqno, seqno);
1420                 orig_ifinfo->last_real_seqno = seqno;
1421         }
1422
1423 out:
1424         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1425         batadv_orig_node_put(orig_node);
1426         batadv_orig_ifinfo_put(orig_ifinfo);
1427         return ret;
1428 }
1429
1430 /**
1431  * batadv_iv_ogm_process_per_outif - process a batman iv OGM for an outgoing if
1432  * @skb: the skb containing the OGM
1433  * @ogm_offset: offset from skb->data to start of ogm header
1434  * @orig_node: the (cached) orig node for the originator of this OGM
1435  * @if_incoming: the interface where this packet was received
1436  * @if_outgoing: the interface for which the packet should be considered
1437  */
1438 static void
1439 batadv_iv_ogm_process_per_outif(const struct sk_buff *skb, int ogm_offset,
1440                                 struct batadv_orig_node *orig_node,
1441                                 struct batadv_hard_iface *if_incoming,
1442                                 struct batadv_hard_iface *if_outgoing)
1443 {
1444         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1445         struct batadv_hardif_neigh_node *hardif_neigh = NULL;
1446         struct batadv_neigh_node *router = NULL;
1447         struct batadv_neigh_node *router_router = NULL;
1448         struct batadv_orig_node *orig_neigh_node;
1449         struct batadv_orig_ifinfo *orig_ifinfo;
1450         struct batadv_neigh_node *orig_neigh_router = NULL;
1451         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
1452         struct batadv_ogm_packet *ogm_packet;
1453         enum batadv_dup_status dup_status;
1454         bool is_from_best_next_hop = false;
1455         bool is_single_hop_neigh = false;
1456         bool sameseq, similar_ttl;
1457         struct sk_buff *skb_priv;
1458         struct ethhdr *ethhdr;
1459         u8 *prev_sender;
1460         bool is_bidirect;
1461
1462         /* create a private copy of the skb, as some functions change tq value
1463          * and/or flags.
1464          */
1465         skb_priv = skb_copy(skb, GFP_ATOMIC);
1466         if (!skb_priv)
1467                 return;
1468
1469         ethhdr = eth_hdr(skb_priv);
1470         ogm_packet = (struct batadv_ogm_packet *)(skb_priv->data + ogm_offset);
1471
1472         dup_status = batadv_iv_ogm_update_seqnos(ethhdr, ogm_packet,
1473                                                  if_incoming, if_outgoing);
1474         if (batadv_compare_eth(ethhdr->h_source, ogm_packet->orig))
1475                 is_single_hop_neigh = true;
1476
1477         if (dup_status == BATADV_PROTECTED) {
1478                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1479                            "Drop packet: packet within seqno protection time (sender: %pM)\n",
1480                            ethhdr->h_source);
1481                 goto out;
1482         }
1483
1484         if (ogm_packet->tq == 0) {
1485                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1486                            "Drop packet: originator packet with tq equal 0\n");
1487                 goto out;
1488         }
1489
1490         if (is_single_hop_neigh) {
1491                 hardif_neigh = batadv_hardif_neigh_get(if_incoming,
1492                                                        ethhdr->h_source);
1493                 if (hardif_neigh)
1494                         hardif_neigh->last_seen = jiffies;
1495         }
1496
1497         router = batadv_orig_router_get(orig_node, if_outgoing);
1498         if (router) {
1499                 router_router = batadv_orig_router_get(router->orig_node,
1500                                                        if_outgoing);
1501                 router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing);
1502         }
1503
1504         if ((router_ifinfo && router_ifinfo->bat_iv.tq_avg != 0) &&
1505             (batadv_compare_eth(router->addr, ethhdr->h_source)))
1506                 is_from_best_next_hop = true;
1507
1508         prev_sender = ogm_packet->prev_sender;
1509         /* avoid temporary routing loops */
1510         if (router && router_router &&
1511             (batadv_compare_eth(router->addr, prev_sender)) &&
1512             !(batadv_compare_eth(ogm_packet->orig, prev_sender)) &&
1513             (batadv_compare_eth(router->addr, router_router->addr))) {
1514                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1515                            "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1516                            ethhdr->h_source);
1517                 goto out;
1518         }
1519
1520         if (if_outgoing == BATADV_IF_DEFAULT)
1521                 batadv_tvlv_ogm_receive(bat_priv, ogm_packet, orig_node);
1522
1523         /* if sender is a direct neighbor the sender mac equals
1524          * originator mac
1525          */
1526         if (is_single_hop_neigh)
1527                 orig_neigh_node = orig_node;
1528         else
1529                 orig_neigh_node = batadv_iv_ogm_orig_get(bat_priv,
1530                                                          ethhdr->h_source);
1531
1532         if (!orig_neigh_node)
1533                 goto out;
1534
1535         /* Update nc_nodes of the originator */
1536         batadv_nc_update_nc_node(bat_priv, orig_node, orig_neigh_node,
1537                                  ogm_packet, is_single_hop_neigh);
1538
1539         orig_neigh_router = batadv_orig_router_get(orig_neigh_node,
1540                                                    if_outgoing);
1541
1542         /* drop packet if sender is not a direct neighbor and if we
1543          * don't route towards it
1544          */
1545         if (!is_single_hop_neigh && (!orig_neigh_router)) {
1546                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1547                            "Drop packet: OGM via unknown neighbor!\n");
1548                 goto out_neigh;
1549         }
1550
1551         is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1552                                             ogm_packet, if_incoming,
1553                                             if_outgoing);
1554
1555         /* update ranking if it is not a duplicate or has the same
1556          * seqno and similar ttl as the non-duplicate
1557          */
1558         orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
1559         if (!orig_ifinfo)
1560                 goto out_neigh;
1561
1562         sameseq = orig_ifinfo->last_real_seqno == ntohl(ogm_packet->seqno);
1563         similar_ttl = (orig_ifinfo->last_ttl - 3) <= ogm_packet->ttl;
1564
1565         if (is_bidirect && ((dup_status == BATADV_NO_DUP) ||
1566                             (sameseq && similar_ttl))) {
1567                 batadv_iv_ogm_orig_update(bat_priv, orig_node,
1568                                           orig_ifinfo, ethhdr,
1569                                           ogm_packet, if_incoming,
1570                                           if_outgoing, dup_status);
1571         }
1572         batadv_orig_ifinfo_put(orig_ifinfo);
1573
1574         /* only forward for specific interface, not for the default one. */
1575         if (if_outgoing == BATADV_IF_DEFAULT)
1576                 goto out_neigh;
1577
1578         /* is single hop (direct) neighbor */
1579         if (is_single_hop_neigh) {
1580                 /* OGMs from secondary interfaces should only scheduled once
1581                  * per interface where it has been received, not multiple times
1582                  */
1583                 if ((ogm_packet->ttl <= 2) &&
1584                     (if_incoming != if_outgoing)) {
1585                         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1586                                    "Drop packet: OGM from secondary interface and wrong outgoing interface\n");
1587                         goto out_neigh;
1588                 }
1589                 /* mark direct link on incoming interface */
1590                 batadv_iv_ogm_forward(orig_node, ethhdr, ogm_packet,
1591                                       is_single_hop_neigh,
1592                                       is_from_best_next_hop, if_incoming,
1593                                       if_outgoing);
1594
1595                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1596                            "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1597                 goto out_neigh;
1598         }
1599
1600         /* multihop originator */
1601         if (!is_bidirect) {
1602                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1603                            "Drop packet: not received via bidirectional link\n");
1604                 goto out_neigh;
1605         }
1606
1607         if (dup_status == BATADV_NEIGH_DUP) {
1608                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1609                            "Drop packet: duplicate packet received\n");
1610                 goto out_neigh;
1611         }
1612
1613         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1614                    "Forwarding packet: rebroadcast originator packet\n");
1615         batadv_iv_ogm_forward(orig_node, ethhdr, ogm_packet,
1616                               is_single_hop_neigh, is_from_best_next_hop,
1617                               if_incoming, if_outgoing);
1618
1619 out_neigh:
1620         if ((orig_neigh_node) && (!is_single_hop_neigh))
1621                 batadv_orig_node_put(orig_neigh_node);
1622 out:
1623         if (router_ifinfo)
1624                 batadv_neigh_ifinfo_put(router_ifinfo);
1625         if (router)
1626                 batadv_neigh_node_put(router);
1627         if (router_router)
1628                 batadv_neigh_node_put(router_router);
1629         if (orig_neigh_router)
1630                 batadv_neigh_node_put(orig_neigh_router);
1631         if (hardif_neigh)
1632                 batadv_hardif_neigh_put(hardif_neigh);
1633
1634         kfree_skb(skb_priv);
1635 }
1636
1637 /**
1638  * batadv_iv_ogm_process - process an incoming batman iv OGM
1639  * @skb: the skb containing the OGM
1640  * @ogm_offset: offset to the OGM which should be processed (for aggregates)
1641  * @if_incoming: the interface where this packet was receved
1642  */
1643 static void batadv_iv_ogm_process(const struct sk_buff *skb, int ogm_offset,
1644                                   struct batadv_hard_iface *if_incoming)
1645 {
1646         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1647         struct batadv_orig_node *orig_neigh_node, *orig_node;
1648         struct batadv_hard_iface *hard_iface;
1649         struct batadv_ogm_packet *ogm_packet;
1650         u32 if_incoming_seqno;
1651         bool has_directlink_flag;
1652         struct ethhdr *ethhdr;
1653         bool is_my_oldorig = false;
1654         bool is_my_addr = false;
1655         bool is_my_orig = false;
1656
1657         ogm_packet = (struct batadv_ogm_packet *)(skb->data + ogm_offset);
1658         ethhdr = eth_hdr(skb);
1659
1660         /* Silently drop when the batman packet is actually not a
1661          * correct packet.
1662          *
1663          * This might happen if a packet is padded (e.g. Ethernet has a
1664          * minimum frame length of 64 byte) and the aggregation interprets
1665          * it as an additional length.
1666          *
1667          * TODO: A more sane solution would be to have a bit in the
1668          * batadv_ogm_packet to detect whether the packet is the last
1669          * packet in an aggregation.  Here we expect that the padding
1670          * is always zero (or not 0x01)
1671          */
1672         if (ogm_packet->packet_type != BATADV_IV_OGM)
1673                 return;
1674
1675         /* could be changed by schedule_own_packet() */
1676         if_incoming_seqno = atomic_read(&if_incoming->bat_iv.ogm_seqno);
1677
1678         if (ogm_packet->flags & BATADV_DIRECTLINK)
1679                 has_directlink_flag = true;
1680         else
1681                 has_directlink_flag = false;
1682
1683         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1684                    "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",
1685                    ethhdr->h_source, if_incoming->net_dev->name,
1686                    if_incoming->net_dev->dev_addr, ogm_packet->orig,
1687                    ogm_packet->prev_sender, ntohl(ogm_packet->seqno),
1688                    ogm_packet->tq, ogm_packet->ttl,
1689                    ogm_packet->version, has_directlink_flag);
1690
1691         rcu_read_lock();
1692         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1693                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
1694                         continue;
1695
1696                 if (hard_iface->soft_iface != if_incoming->soft_iface)
1697                         continue;
1698
1699                 if (batadv_compare_eth(ethhdr->h_source,
1700                                        hard_iface->net_dev->dev_addr))
1701                         is_my_addr = true;
1702
1703                 if (batadv_compare_eth(ogm_packet->orig,
1704                                        hard_iface->net_dev->dev_addr))
1705                         is_my_orig = true;
1706
1707                 if (batadv_compare_eth(ogm_packet->prev_sender,
1708                                        hard_iface->net_dev->dev_addr))
1709                         is_my_oldorig = true;
1710         }
1711         rcu_read_unlock();
1712
1713         if (is_my_addr) {
1714                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1715                            "Drop packet: received my own broadcast (sender: %pM)\n",
1716                            ethhdr->h_source);
1717                 return;
1718         }
1719
1720         if (is_my_orig) {
1721                 unsigned long *word;
1722                 int offset;
1723                 s32 bit_pos;
1724                 s16 if_num;
1725                 u8 *weight;
1726
1727                 orig_neigh_node = batadv_iv_ogm_orig_get(bat_priv,
1728                                                          ethhdr->h_source);
1729                 if (!orig_neigh_node)
1730                         return;
1731
1732                 /* neighbor has to indicate direct link and it has to
1733                  * come via the corresponding interface
1734                  * save packet seqno for bidirectional check
1735                  */
1736                 if (has_directlink_flag &&
1737                     batadv_compare_eth(if_incoming->net_dev->dev_addr,
1738                                        ogm_packet->orig)) {
1739                         if_num = if_incoming->if_num;
1740                         offset = if_num * BATADV_NUM_WORDS;
1741
1742                         spin_lock_bh(&orig_neigh_node->bat_iv.ogm_cnt_lock);
1743                         word = &orig_neigh_node->bat_iv.bcast_own[offset];
1744                         bit_pos = if_incoming_seqno - 2;
1745                         bit_pos -= ntohl(ogm_packet->seqno);
1746                         batadv_set_bit(word, bit_pos);
1747                         weight = &orig_neigh_node->bat_iv.bcast_own_sum[if_num];
1748                         *weight = bitmap_weight(word,
1749                                                 BATADV_TQ_LOCAL_WINDOW_SIZE);
1750                         spin_unlock_bh(&orig_neigh_node->bat_iv.ogm_cnt_lock);
1751                 }
1752
1753                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1754                            "Drop packet: originator packet from myself (via neighbor)\n");
1755                 batadv_orig_node_put(orig_neigh_node);
1756                 return;
1757         }
1758
1759         if (is_my_oldorig) {
1760                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1761                            "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1762                            ethhdr->h_source);
1763                 return;
1764         }
1765
1766         if (ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) {
1767                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1768                            "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1769                            ethhdr->h_source);
1770                 return;
1771         }
1772
1773         orig_node = batadv_iv_ogm_orig_get(bat_priv, ogm_packet->orig);
1774         if (!orig_node)
1775                 return;
1776
1777         batadv_iv_ogm_process_per_outif(skb, ogm_offset, orig_node,
1778                                         if_incoming, BATADV_IF_DEFAULT);
1779
1780         rcu_read_lock();
1781         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1782                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
1783                         continue;
1784
1785                 if (hard_iface->soft_iface != bat_priv->soft_iface)
1786                         continue;
1787
1788                 if (!kref_get_unless_zero(&hard_iface->refcount))
1789                         continue;
1790
1791                 batadv_iv_ogm_process_per_outif(skb, ogm_offset, orig_node,
1792                                                 if_incoming, hard_iface);
1793
1794                 batadv_hardif_put(hard_iface);
1795         }
1796         rcu_read_unlock();
1797
1798         batadv_orig_node_put(orig_node);
1799 }
1800
1801 static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work)
1802 {
1803         struct delayed_work *delayed_work;
1804         struct batadv_forw_packet *forw_packet;
1805         struct batadv_priv *bat_priv;
1806
1807         delayed_work = to_delayed_work(work);
1808         forw_packet = container_of(delayed_work, struct batadv_forw_packet,
1809                                    delayed_work);
1810         bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface);
1811         spin_lock_bh(&bat_priv->forw_bat_list_lock);
1812         hlist_del(&forw_packet->list);
1813         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
1814
1815         if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
1816                 goto out;
1817
1818         batadv_iv_ogm_emit(forw_packet);
1819
1820         /* we have to have at least one packet in the queue to determine the
1821          * queues wake up time unless we are shutting down.
1822          *
1823          * only re-schedule if this is the "original" copy, e.g. the OGM of the
1824          * primary interface should only be rescheduled once per period, but
1825          * this function will be called for the forw_packet instances of the
1826          * other secondary interfaces as well.
1827          */
1828         if (forw_packet->own &&
1829             forw_packet->if_incoming == forw_packet->if_outgoing)
1830                 batadv_iv_ogm_schedule(forw_packet->if_incoming);
1831
1832 out:
1833         /* don't count own packet */
1834         if (!forw_packet->own)
1835                 atomic_inc(&bat_priv->batman_queue_left);
1836
1837         batadv_forw_packet_free(forw_packet);
1838 }
1839
1840 static int batadv_iv_ogm_receive(struct sk_buff *skb,
1841                                  struct batadv_hard_iface *if_incoming)
1842 {
1843         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1844         struct batadv_ogm_packet *ogm_packet;
1845         u8 *packet_pos;
1846         int ogm_offset;
1847         bool ret;
1848
1849         ret = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
1850         if (!ret)
1851                 return NET_RX_DROP;
1852
1853         /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1854          * that does not have B.A.T.M.A.N. IV enabled ?
1855          */
1856         if (bat_priv->algo_ops->iface.enable != batadv_iv_ogm_iface_enable)
1857                 return NET_RX_DROP;
1858
1859         batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
1860         batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
1861                            skb->len + ETH_HLEN);
1862
1863         ogm_offset = 0;
1864         ogm_packet = (struct batadv_ogm_packet *)skb->data;
1865
1866         /* unpack the aggregated packets and process them one by one */
1867         while (batadv_iv_ogm_aggr_packet(ogm_offset, skb_headlen(skb),
1868                                          ogm_packet->tvlv_len)) {
1869                 batadv_iv_ogm_process(skb, ogm_offset, if_incoming);
1870
1871                 ogm_offset += BATADV_OGM_HLEN;
1872                 ogm_offset += ntohs(ogm_packet->tvlv_len);
1873
1874                 packet_pos = skb->data + ogm_offset;
1875                 ogm_packet = (struct batadv_ogm_packet *)packet_pos;
1876         }
1877
1878         kfree_skb(skb);
1879         return NET_RX_SUCCESS;
1880 }
1881
1882 /**
1883  * batadv_iv_ogm_orig_print_neigh - print neighbors for the originator table
1884  * @orig_node: the orig_node for which the neighbors are printed
1885  * @if_outgoing: outgoing interface for these entries
1886  * @seq: debugfs table seq_file struct
1887  *
1888  * Must be called while holding an rcu lock.
1889  */
1890 static void
1891 batadv_iv_ogm_orig_print_neigh(struct batadv_orig_node *orig_node,
1892                                struct batadv_hard_iface *if_outgoing,
1893                                struct seq_file *seq)
1894 {
1895         struct batadv_neigh_node *neigh_node;
1896         struct batadv_neigh_ifinfo *n_ifinfo;
1897
1898         hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
1899                 n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
1900                 if (!n_ifinfo)
1901                         continue;
1902
1903                 seq_printf(seq, " %pM (%3i)",
1904                            neigh_node->addr,
1905                            n_ifinfo->bat_iv.tq_avg);
1906
1907                 batadv_neigh_ifinfo_put(n_ifinfo);
1908         }
1909 }
1910
1911 /**
1912  * batadv_iv_ogm_orig_print - print the originator table
1913  * @bat_priv: the bat priv with all the soft interface information
1914  * @seq: debugfs table seq_file struct
1915  * @if_outgoing: the outgoing interface for which this should be printed
1916  */
1917 static void batadv_iv_ogm_orig_print(struct batadv_priv *bat_priv,
1918                                      struct seq_file *seq,
1919                                      struct batadv_hard_iface *if_outgoing)
1920 {
1921         struct batadv_neigh_node *neigh_node;
1922         struct batadv_hashtable *hash = bat_priv->orig_hash;
1923         int last_seen_msecs, last_seen_secs;
1924         struct batadv_orig_node *orig_node;
1925         struct batadv_neigh_ifinfo *n_ifinfo;
1926         unsigned long last_seen_jiffies;
1927         struct hlist_head *head;
1928         int batman_count = 0;
1929         u32 i;
1930
1931         seq_puts(seq,
1932                  "  Originator      last-seen (#/255)           Nexthop [outgoingIF]:   Potential nexthops ...\n");
1933
1934         for (i = 0; i < hash->size; i++) {
1935                 head = &hash->table[i];
1936
1937                 rcu_read_lock();
1938                 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
1939                         neigh_node = batadv_orig_router_get(orig_node,
1940                                                             if_outgoing);
1941                         if (!neigh_node)
1942                                 continue;
1943
1944                         n_ifinfo = batadv_neigh_ifinfo_get(neigh_node,
1945                                                            if_outgoing);
1946                         if (!n_ifinfo)
1947                                 goto next;
1948
1949                         if (n_ifinfo->bat_iv.tq_avg == 0)
1950                                 goto next;
1951
1952                         last_seen_jiffies = jiffies - orig_node->last_seen;
1953                         last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
1954                         last_seen_secs = last_seen_msecs / 1000;
1955                         last_seen_msecs = last_seen_msecs % 1000;
1956
1957                         seq_printf(seq, "%pM %4i.%03is   (%3i) %pM [%10s]:",
1958                                    orig_node->orig, last_seen_secs,
1959                                    last_seen_msecs, n_ifinfo->bat_iv.tq_avg,
1960                                    neigh_node->addr,
1961                                    neigh_node->if_incoming->net_dev->name);
1962
1963                         batadv_iv_ogm_orig_print_neigh(orig_node, if_outgoing,
1964                                                        seq);
1965                         seq_puts(seq, "\n");
1966                         batman_count++;
1967
1968 next:
1969                         batadv_neigh_node_put(neigh_node);
1970                         if (n_ifinfo)
1971                                 batadv_neigh_ifinfo_put(n_ifinfo);
1972                 }
1973                 rcu_read_unlock();
1974         }
1975
1976         if (batman_count == 0)
1977                 seq_puts(seq, "No batman nodes in range ...\n");
1978 }
1979
1980 /**
1981  * batadv_iv_hardif_neigh_print - print a single hop neighbour node
1982  * @seq: neighbour table seq_file struct
1983  * @hardif_neigh: hardif neighbour information
1984  */
1985 static void
1986 batadv_iv_hardif_neigh_print(struct seq_file *seq,
1987                              struct batadv_hardif_neigh_node *hardif_neigh)
1988 {
1989         int last_secs, last_msecs;
1990
1991         last_secs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen) / 1000;
1992         last_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen) % 1000;
1993
1994         seq_printf(seq, "   %10s   %pM %4i.%03is\n",
1995                    hardif_neigh->if_incoming->net_dev->name,
1996                    hardif_neigh->addr, last_secs, last_msecs);
1997 }
1998
1999 /**
2000  * batadv_iv_ogm_neigh_print - print the single hop neighbour list
2001  * @bat_priv: the bat priv with all the soft interface information
2002  * @seq: neighbour table seq_file struct
2003  */
2004 static void batadv_iv_neigh_print(struct batadv_priv *bat_priv,
2005                                   struct seq_file *seq)
2006 {
2007         struct net_device *net_dev = (struct net_device *)seq->private;
2008         struct batadv_hardif_neigh_node *hardif_neigh;
2009         struct batadv_hard_iface *hard_iface;
2010         int batman_count = 0;
2011
2012         seq_puts(seq, "           IF        Neighbor      last-seen\n");
2013
2014         rcu_read_lock();
2015         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
2016                 if (hard_iface->soft_iface != net_dev)
2017                         continue;
2018
2019                 hlist_for_each_entry_rcu(hardif_neigh,
2020                                          &hard_iface->neigh_list, list) {
2021                         batadv_iv_hardif_neigh_print(seq, hardif_neigh);
2022                         batman_count++;
2023                 }
2024         }
2025         rcu_read_unlock();
2026
2027         if (batman_count == 0)
2028                 seq_puts(seq, "No batman nodes in range ...\n");
2029 }
2030
2031 /**
2032  * batadv_iv_ogm_neigh_cmp - compare the metrics of two neighbors
2033  * @neigh1: the first neighbor object of the comparison
2034  * @if_outgoing1: outgoing interface for the first neighbor
2035  * @neigh2: the second neighbor object of the comparison
2036  * @if_outgoing2: outgoing interface for the second neighbor
2037  *
2038  * Return: a value less, equal to or greater than 0 if the metric via neigh1 is
2039  * lower, the same as or higher than the metric via neigh2
2040  */
2041 static int batadv_iv_ogm_neigh_cmp(struct batadv_neigh_node *neigh1,
2042                                    struct batadv_hard_iface *if_outgoing1,
2043                                    struct batadv_neigh_node *neigh2,
2044                                    struct batadv_hard_iface *if_outgoing2)
2045 {
2046         struct batadv_neigh_ifinfo *neigh1_ifinfo, *neigh2_ifinfo;
2047         u8 tq1, tq2;
2048         int diff;
2049
2050         neigh1_ifinfo = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
2051         neigh2_ifinfo = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
2052
2053         if (!neigh1_ifinfo || !neigh2_ifinfo) {
2054                 diff = 0;
2055                 goto out;
2056         }
2057
2058         tq1 = neigh1_ifinfo->bat_iv.tq_avg;
2059         tq2 = neigh2_ifinfo->bat_iv.tq_avg;
2060         diff = tq1 - tq2;
2061
2062 out:
2063         if (neigh1_ifinfo)
2064                 batadv_neigh_ifinfo_put(neigh1_ifinfo);
2065         if (neigh2_ifinfo)
2066                 batadv_neigh_ifinfo_put(neigh2_ifinfo);
2067
2068         return diff;
2069 }
2070
2071 /**
2072  * batadv_iv_ogm_neigh_is_sob - check if neigh1 is similarly good or better
2073  *  than neigh2 from the metric prospective
2074  * @neigh1: the first neighbor object of the comparison
2075  * @if_outgoing1: outgoing interface for the first neighbor
2076  * @neigh2: the second neighbor object of the comparison
2077  * @if_outgoing2: outgoing interface for the second neighbor
2078  *
2079  * Return: true if the metric via neigh1 is equally good or better than
2080  * the metric via neigh2, false otherwise.
2081  */
2082 static bool
2083 batadv_iv_ogm_neigh_is_sob(struct batadv_neigh_node *neigh1,
2084                            struct batadv_hard_iface *if_outgoing1,
2085                            struct batadv_neigh_node *neigh2,
2086                            struct batadv_hard_iface *if_outgoing2)
2087 {
2088         struct batadv_neigh_ifinfo *neigh1_ifinfo, *neigh2_ifinfo;
2089         u8 tq1, tq2;
2090         bool ret;
2091
2092         neigh1_ifinfo = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
2093         neigh2_ifinfo = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
2094
2095         /* we can't say that the metric is better */
2096         if (!neigh1_ifinfo || !neigh2_ifinfo) {
2097                 ret = false;
2098                 goto out;
2099         }
2100
2101         tq1 = neigh1_ifinfo->bat_iv.tq_avg;
2102         tq2 = neigh2_ifinfo->bat_iv.tq_avg;
2103         ret = (tq1 - tq2) > -BATADV_TQ_SIMILARITY_THRESHOLD;
2104
2105 out:
2106         if (neigh1_ifinfo)
2107                 batadv_neigh_ifinfo_put(neigh1_ifinfo);
2108         if (neigh2_ifinfo)
2109                 batadv_neigh_ifinfo_put(neigh2_ifinfo);
2110
2111         return ret;
2112 }
2113
2114 static void batadv_iv_iface_activate(struct batadv_hard_iface *hard_iface)
2115 {
2116         /* begin scheduling originator messages on that interface */
2117         batadv_iv_ogm_schedule(hard_iface);
2118 }
2119
2120 static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
2121         .name = "BATMAN_IV",
2122         .iface = {
2123                 .activate = batadv_iv_iface_activate,
2124                 .enable = batadv_iv_ogm_iface_enable,
2125                 .disable = batadv_iv_ogm_iface_disable,
2126                 .update_mac = batadv_iv_ogm_iface_update_mac,
2127                 .primary_set = batadv_iv_ogm_primary_iface_set,
2128         },
2129         .neigh = {
2130                 .cmp = batadv_iv_ogm_neigh_cmp,
2131                 .is_similar_or_better = batadv_iv_ogm_neigh_is_sob,
2132                 .print = batadv_iv_neigh_print,
2133         },
2134         .orig = {
2135                 .print = batadv_iv_ogm_orig_print,
2136                 .free = batadv_iv_ogm_orig_free,
2137                 .add_if = batadv_iv_ogm_orig_add_if,
2138                 .del_if = batadv_iv_ogm_orig_del_if,
2139         },
2140 };
2141
2142 int __init batadv_iv_init(void)
2143 {
2144         int ret;
2145
2146         /* batman originator packet */
2147         ret = batadv_recv_handler_register(BATADV_IV_OGM,
2148                                            batadv_iv_ogm_receive);
2149         if (ret < 0)
2150                 goto out;
2151
2152         ret = batadv_algo_register(&batadv_batman_iv);
2153         if (ret < 0)
2154                 goto handler_unregister;
2155
2156         goto out;
2157
2158 handler_unregister:
2159         batadv_recv_handler_unregister(BATADV_IV_OGM);
2160 out:
2161         return ret;
2162 }