net/batman-adv/bat_v.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (C) 2013-2017  B.A.T.M.A.N. contributors:
   3  *
   4  * Linus Lüssing, Marek Lindner
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of version 2 of the GNU General Public
   8  * License as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include "bat_v.h"
  20 #include "main.h"
  21
  22 #include <linux/atomic.h>
  23 #include <linux/cache.h>
  24 #include <linux/errno.h>
  25 #include <linux/if_ether.h>
  26 #include <linux/init.h>
  27 #include <linux/jiffies.h>
  28 #include <linux/kernel.h>
  29 #include <linux/kref.h>
  30 #include <linux/netdevice.h>
  31 #include <linux/netlink.h>
  32 #include <linux/rculist.h>
  33 #include <linux/rcupdate.h>
  34 #include <linux/seq_file.h>
  35 #include <linux/stddef.h>
  36 #include <linux/types.h>
  37 #include <linux/workqueue.h>
  38 #include <net/genetlink.h>
  39 #include <net/netlink.h>
  40 #include <uapi/linux/batadv_packet.h>
  41 #include <uapi/linux/batman_adv.h>
  42
  43 #include "bat_algo.h"
  44 #include "bat_v_elp.h"
  45 #include "bat_v_ogm.h"
  46 #include "gateway_client.h"
  47 #include "gateway_common.h"
  48 #include "hard-interface.h"
  49 #include "hash.h"
  50 #include "log.h"
  51 #include "netlink.h"
  52 #include "originator.h"
  53
  54 struct sk_buff;
  55
  56 static void batadv_v_iface_activate(struct batadv_hard_iface *hard_iface)
  57 {
  58         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
  59         struct batadv_hard_iface *primary_if;
  60
  61         primary_if = batadv_primary_if_get_selected(bat_priv);
  62
  63         if (primary_if) {
  64                 batadv_v_elp_iface_activate(primary_if, hard_iface);
  65                 batadv_hardif_put(primary_if);
  66         }
  67
  68         /* B.A.T.M.A.N. V does not use any queuing mechanism, therefore it can
  69          * set the interface as ACTIVE right away, without any risk of race
  70          * condition
  71          */
  72         if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED)
  73                 hard_iface->if_status = BATADV_IF_ACTIVE;
  74 }
  75
  76 static int batadv_v_iface_enable(struct batadv_hard_iface *hard_iface)
  77 {
  78         int ret;
  79
  80         ret = batadv_v_elp_iface_enable(hard_iface);
  81         if (ret < 0)
  82                 return ret;
  83
  84         ret = batadv_v_ogm_iface_enable(hard_iface);
  85         if (ret < 0)
  86                 batadv_v_elp_iface_disable(hard_iface);
  87
  88         return ret;
  89 }
  90
  91 static void batadv_v_iface_disable(struct batadv_hard_iface *hard_iface)
  92 {
  93         batadv_v_elp_iface_disable(hard_iface);
  94 }
  95
  96 static void batadv_v_primary_iface_set(struct batadv_hard_iface *hard_iface)
  97 {
  98         batadv_v_elp_primary_iface_set(hard_iface);
  99         batadv_v_ogm_primary_iface_set(hard_iface);
 100 }
 101
 102 /**
 103  * batadv_v_iface_update_mac() - react to hard-interface MAC address change
 104  * @hard_iface: the modified interface
 105  *
 106  * If the modified interface is the primary one, update the originator
 107  * address in the ELP and OGM messages to reflect the new MAC address.
 108  */
 109 static void batadv_v_iface_update_mac(struct batadv_hard_iface *hard_iface)
 110 {
 111         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 112         struct batadv_hard_iface *primary_if;
 113
 114         primary_if = batadv_primary_if_get_selected(bat_priv);
 115         if (primary_if != hard_iface)
 116                 goto out;
 117
 118         batadv_v_primary_iface_set(hard_iface);
 119 out:
 120         if (primary_if)
 121                 batadv_hardif_put(primary_if);
 122 }
 123
 124 static void
 125 batadv_v_hardif_neigh_init(struct batadv_hardif_neigh_node *hardif_neigh)
 126 {
 127         ewma_throughput_init(&hardif_neigh->bat_v.throughput);
 128         INIT_WORK(&hardif_neigh->bat_v.metric_work,
 129                   batadv_v_elp_throughput_metric_update);
 130 }
 131
 132 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
 133 /**
 134  * batadv_v_orig_print_neigh() - print neighbors for the originator table
 135  * @orig_node: the orig_node for which the neighbors are printed
 136  * @if_outgoing: outgoing interface for these entries
 137  * @seq: debugfs table seq_file struct
 138  *
 139  * Must be called while holding an rcu lock.
 140  */
 141 static void
 142 batadv_v_orig_print_neigh(struct batadv_orig_node *orig_node,
 143                           struct batadv_hard_iface *if_outgoing,
 144                           struct seq_file *seq)
 145 {
 146         struct batadv_neigh_node *neigh_node;
 147         struct batadv_neigh_ifinfo *n_ifinfo;
 148
 149         hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
 150                 n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
 151                 if (!n_ifinfo)
 152                         continue;
 153
 154                 seq_printf(seq, " %pM (%9u.%1u)",
 155                            neigh_node->addr,
 156                            n_ifinfo->bat_v.throughput / 10,
 157                            n_ifinfo->bat_v.throughput % 10);
 158
 159                 batadv_neigh_ifinfo_put(n_ifinfo);
 160         }
 161 }
 162
 163 /**
 164  * batadv_v_hardif_neigh_print() - print a single ELP neighbour node
 165  * @seq: neighbour table seq_file struct
 166  * @hardif_neigh: hardif neighbour information
 167  */
 168 static void
 169 batadv_v_hardif_neigh_print(struct seq_file *seq,
 170                             struct batadv_hardif_neigh_node *hardif_neigh)
 171 {
 172         int last_secs, last_msecs;
 173         u32 throughput;
 174
 175         last_secs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen) / 1000;
 176         last_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen) % 1000;
 177         throughput = ewma_throughput_read(&hardif_neigh->bat_v.throughput);
 178
 179         seq_printf(seq, "%pM %4i.%03is (%9u.%1u) [%10s]\n",
 180                    hardif_neigh->addr, last_secs, last_msecs, throughput / 10,
 181                    throughput % 10, hardif_neigh->if_incoming->net_dev->name);
 182 }
 183
 184 /**
 185  * batadv_v_neigh_print() - print the single hop neighbour list
 186  * @bat_priv: the bat priv with all the soft interface information
 187  * @seq: neighbour table seq_file struct
 188  */
 189 static void batadv_v_neigh_print(struct batadv_priv *bat_priv,
 190                                  struct seq_file *seq)
 191 {
 192         struct net_device *net_dev = (struct net_device *)seq->private;
 193         struct batadv_hardif_neigh_node *hardif_neigh;
 194         struct batadv_hard_iface *hard_iface;
 195         int batman_count = 0;
 196
 197         seq_puts(seq,
 198                  "  Neighbor        last-seen ( throughput) [        IF]\n");
 199
 200         rcu_read_lock();
 201         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 202                 if (hard_iface->soft_iface != net_dev)
 203                         continue;
 204
 205                 hlist_for_each_entry_rcu(hardif_neigh,
 206                                          &hard_iface->neigh_list, list) {
 207                         batadv_v_hardif_neigh_print(seq, hardif_neigh);
 208                         batman_count++;
 209                 }
 210         }
 211         rcu_read_unlock();
 212
 213         if (batman_count == 0)
 214                 seq_puts(seq, "No batman nodes in range ...\n");
 215 }
 216 #endif
 217
 218 /**
 219  * batadv_v_neigh_dump_neigh() - Dump a neighbour into a message
 220  * @msg: Netlink message to dump into
 221  * @portid: Port making netlink request
 222  * @seq: Sequence number of netlink message
 223  * @hardif_neigh: Neighbour to dump
 224  *
 225  * Return: Error code, or 0 on success
 226  */
 227 static int
 228 batadv_v_neigh_dump_neigh(struct sk_buff *msg, u32 portid, u32 seq,
 229                           struct batadv_hardif_neigh_node *hardif_neigh)
 230 {
 231         void *hdr;
 232         unsigned int last_seen_msecs;
 233         u32 throughput;
 234
 235         last_seen_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen);
 236         throughput = ewma_throughput_read(&hardif_neigh->bat_v.throughput);
 237         throughput = throughput * 100;
 238
 239         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, NLM_F_MULTI,
 240                           BATADV_CMD_GET_NEIGHBORS);
 241         if (!hdr)
 242                 return -ENOBUFS;
 243
 244         if (nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
 245                     hardif_neigh->addr) ||
 246             nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
 247                         hardif_neigh->if_incoming->net_dev->ifindex) ||
 248             nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
 249                         last_seen_msecs) ||
 250             nla_put_u32(msg, BATADV_ATTR_THROUGHPUT, throughput))
 251                 goto nla_put_failure;
 252
 253         genlmsg_end(msg, hdr);
 254         return 0;
 255
 256  nla_put_failure:
 257         genlmsg_cancel(msg, hdr);
 258         return -EMSGSIZE;
 259 }
 260
 261 /**
 262  * batadv_v_neigh_dump_hardif() - Dump the  neighbours of a hard interface into
 263  *  a message
 264  * @msg: Netlink message to dump into
 265  * @portid: Port making netlink request
 266  * @seq: Sequence number of netlink message
 267  * @bat_priv: The bat priv with all the soft interface information
 268  * @hard_iface: The hard interface to be dumped
 269  * @idx_s: Entries to be skipped
 270  *
 271  * This function assumes the caller holds rcu_read_lock().
 272  *
 273  * Return: Error code, or 0 on success
 274  */
 275 static int
 276 batadv_v_neigh_dump_hardif(struct sk_buff *msg, u32 portid, u32 seq,
 277                            struct batadv_priv *bat_priv,
 278                            struct batadv_hard_iface *hard_iface,
 279                            int *idx_s)
 280 {
 281         struct batadv_hardif_neigh_node *hardif_neigh;
 282         int idx = 0;
 283
 284         hlist_for_each_entry_rcu(hardif_neigh,
 285                                  &hard_iface->neigh_list, list) {
 286                 if (idx++ < *idx_s)
 287                         continue;
 288
 289                 if (batadv_v_neigh_dump_neigh(msg, portid, seq, hardif_neigh)) {
 290                         *idx_s = idx - 1;
 291                         return -EMSGSIZE;
 292                 }
 293         }
 294
 295         *idx_s = 0;
 296         return 0;
 297 }
 298
 299 /**
 300  * batadv_v_neigh_dump() - Dump the neighbours of a hard interface  into a
 301  *  message
 302  * @msg: Netlink message to dump into
 303  * @cb: Control block containing additional options
 304  * @bat_priv: The bat priv with all the soft interface information
 305  * @single_hardif: Limit dumping to this hard interface
 306  */
 307 static void
 308 batadv_v_neigh_dump(struct sk_buff *msg, struct netlink_callback *cb,
 309                     struct batadv_priv *bat_priv,
 310                     struct batadv_hard_iface *single_hardif)
 311 {
 312         struct batadv_hard_iface *hard_iface;
 313         int i_hardif = 0;
 314         int i_hardif_s = cb->args[0];
 315         int idx = cb->args[1];
 316         int portid = NETLINK_CB(cb->skb).portid;
 317
 318         rcu_read_lock();
 319         if (single_hardif) {
 320                 if (i_hardif_s == 0) {
 321                         if (batadv_v_neigh_dump_hardif(msg, portid,
 322                                                        cb->nlh->nlmsg_seq,
 323                                                        bat_priv, single_hardif,
 324                                                        &idx) == 0)
 325                                 i_hardif++;
 326                 }
 327         } else {
 328                 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 329                         if (hard_iface->soft_iface != bat_priv->soft_iface)
 330                                 continue;
 331
 332                         if (i_hardif++ < i_hardif_s)
 333                                 continue;
 334
 335                         if (batadv_v_neigh_dump_hardif(msg, portid,
 336                                                        cb->nlh->nlmsg_seq,
 337                                                        bat_priv, hard_iface,
 338                                                        &idx)) {
 339                                 i_hardif--;
 340                                 break;
 341                         }
 342                 }
 343         }
 344         rcu_read_unlock();
 345
 346         cb->args[0] = i_hardif;
 347         cb->args[1] = idx;
 348 }
 349
 350 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
 351 /**
 352  * batadv_v_orig_print() - print the originator table
 353  * @bat_priv: the bat priv with all the soft interface information
 354  * @seq: debugfs table seq_file struct
 355  * @if_outgoing: the outgoing interface for which this should be printed
 356  */
 357 static void batadv_v_orig_print(struct batadv_priv *bat_priv,
 358                                 struct seq_file *seq,
 359                                 struct batadv_hard_iface *if_outgoing)
 360 {
 361         struct batadv_neigh_node *neigh_node;
 362         struct batadv_hashtable *hash = bat_priv->orig_hash;
 363         int last_seen_msecs, last_seen_secs;
 364         struct batadv_orig_node *orig_node;
 365         struct batadv_neigh_ifinfo *n_ifinfo;
 366         unsigned long last_seen_jiffies;
 367         struct hlist_head *head;
 368         int batman_count = 0;
 369         u32 i;
 370
 371         seq_puts(seq,
 372                  "  Originator      last-seen ( throughput)           Nexthop [outgoingIF]:   Potential nexthops ...\n");
 373
 374         for (i = 0; i < hash->size; i++) {
 375                 head = &hash->table[i];
 376
 377                 rcu_read_lock();
 378                 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
 379                         neigh_node = batadv_orig_router_get(orig_node,
 380                                                             if_outgoing);
 381                         if (!neigh_node)
 382                                 continue;
 383
 384                         n_ifinfo = batadv_neigh_ifinfo_get(neigh_node,
 385                                                            if_outgoing);
 386                         if (!n_ifinfo)
 387                                 goto next;
 388
 389                         last_seen_jiffies = jiffies - orig_node->last_seen;
 390                         last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
 391                         last_seen_secs = last_seen_msecs / 1000;
 392                         last_seen_msecs = last_seen_msecs % 1000;
 393
 394                         seq_printf(seq, "%pM %4i.%03is (%9u.%1u) %pM [%10s]:",
 395                                    orig_node->orig, last_seen_secs,
 396                                    last_seen_msecs,
 397                                    n_ifinfo->bat_v.throughput / 10,
 398                                    n_ifinfo->bat_v.throughput % 10,
 399                                    neigh_node->addr,
 400                                    neigh_node->if_incoming->net_dev->name);
 401
 402                         batadv_v_orig_print_neigh(orig_node, if_outgoing, seq);
 403                         seq_putc(seq, '\n');
 404                         batman_count++;
 405
 406 next:
 407                         batadv_neigh_node_put(neigh_node);
 408                         if (n_ifinfo)
 409                                 batadv_neigh_ifinfo_put(n_ifinfo);
 410                 }
 411                 rcu_read_unlock();
 412         }
 413
 414         if (batman_count == 0)
 415                 seq_puts(seq, "No batman nodes in range ...\n");
 416 }
 417 #endif
 418
 419 /**
 420  * batadv_v_orig_dump_subentry() - Dump an originator subentry into a message
 421  * @msg: Netlink message to dump into
 422  * @portid: Port making netlink request
 423  * @seq: Sequence number of netlink message
 424  * @bat_priv: The bat priv with all the soft interface information
 425  * @if_outgoing: Limit dump to entries with this outgoing interface
 426  * @orig_node: Originator to dump
 427  * @neigh_node: Single hops neighbour
 428  * @best: Is the best originator
 429  *
 430  * Return: Error code, or 0 on success
 431  */
 432 static int
 433 batadv_v_orig_dump_subentry(struct sk_buff *msg, u32 portid, u32 seq,
 434                             struct batadv_priv *bat_priv,
 435                             struct batadv_hard_iface *if_outgoing,
 436                             struct batadv_orig_node *orig_node,
 437                             struct batadv_neigh_node *neigh_node,
 438                             bool best)
 439 {
 440         struct batadv_neigh_ifinfo *n_ifinfo;
 441         unsigned int last_seen_msecs;
 442         u32 throughput;
 443         void *hdr;
 444
 445         n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
 446         if (!n_ifinfo)
 447                 return 0;
 448
 449         throughput = n_ifinfo->bat_v.throughput * 100;
 450
 451         batadv_neigh_ifinfo_put(n_ifinfo);
 452
 453         last_seen_msecs = jiffies_to_msecs(jiffies - orig_node->last_seen);
 454
 455         if (if_outgoing != BATADV_IF_DEFAULT &&
 456             if_outgoing != neigh_node->if_incoming)
 457                 return 0;
 458
 459         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, NLM_F_MULTI,
 460                           BATADV_CMD_GET_ORIGINATORS);
 461         if (!hdr)
 462                 return -ENOBUFS;
 463
 464         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN, orig_node->orig) ||
 465             nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
 466                     neigh_node->addr) ||
 467             nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
 468                         neigh_node->if_incoming->net_dev->ifindex) ||
 469             nla_put_u32(msg, BATADV_ATTR_THROUGHPUT, throughput) ||
 470             nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
 471                         last_seen_msecs))
 472                 goto nla_put_failure;
 473
 474         if (best && nla_put_flag(msg, BATADV_ATTR_FLAG_BEST))
 475                 goto nla_put_failure;
 476
 477         genlmsg_end(msg, hdr);
 478         return 0;
 479
 480  nla_put_failure:
 481         genlmsg_cancel(msg, hdr);
 482         return -EMSGSIZE;
 483 }
 484
 485 /**
 486  * batadv_v_orig_dump_entry() - Dump an originator entry into a message
 487  * @msg: Netlink message to dump into
 488  * @portid: Port making netlink request
 489  * @seq: Sequence number of netlink message
 490  * @bat_priv: The bat priv with all the soft interface information
 491  * @if_outgoing: Limit dump to entries with this outgoing interface
 492  * @orig_node: Originator to dump
 493  * @sub_s: Number of sub entries to skip
 494  *
 495  * This function assumes the caller holds rcu_read_lock().
 496  *
 497  * Return: Error code, or 0 on success
 498  */
 499 static int
 500 batadv_v_orig_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
 501                          struct batadv_priv *bat_priv,
 502                          struct batadv_hard_iface *if_outgoing,
 503                          struct batadv_orig_node *orig_node, int *sub_s)
 504 {
 505         struct batadv_neigh_node *neigh_node_best;
 506         struct batadv_neigh_node *neigh_node;
 507         int sub = 0;
 508         bool best;
 509
 510         neigh_node_best = batadv_orig_router_get(orig_node, if_outgoing);
 511         if (!neigh_node_best)
 512                 goto out;
 513
 514         hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
 515                 if (sub++ < *sub_s)
 516                         continue;
 517
 518                 best = (neigh_node == neigh_node_best);
 519
 520                 if (batadv_v_orig_dump_subentry(msg, portid, seq, bat_priv,
 521                                                 if_outgoing, orig_node,
 522                                                 neigh_node, best)) {
 523                         batadv_neigh_node_put(neigh_node_best);
 524
 525                         *sub_s = sub - 1;
 526                         return -EMSGSIZE;
 527                 }
 528         }
 529
 530  out:
 531         if (neigh_node_best)
 532                 batadv_neigh_node_put(neigh_node_best);
 533
 534         *sub_s = 0;
 535         return 0;
 536 }
 537
 538 /**
 539  * batadv_v_orig_dump_bucket() - Dump an originator bucket into a message
 540  * @msg: Netlink message to dump into
 541  * @portid: Port making netlink request
 542  * @seq: Sequence number of netlink message
 543  * @bat_priv: The bat priv with all the soft interface information
 544  * @if_outgoing: Limit dump to entries with this outgoing interface
 545  * @head: Bucket to be dumped
 546  * @idx_s: Number of entries to be skipped
 547  * @sub: Number of sub entries to be skipped
 548  *
 549  * Return: Error code, or 0 on success
 550  */
 551 static int
 552 batadv_v_orig_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
 553                           struct batadv_priv *bat_priv,
 554                           struct batadv_hard_iface *if_outgoing,
 555                           struct hlist_head *head, int *idx_s, int *sub)
 556 {
 557         struct batadv_orig_node *orig_node;
 558         int idx = 0;
 559
 560         rcu_read_lock();
 561         hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
 562                 if (idx++ < *idx_s)
 563                         continue;
 564
 565                 if (batadv_v_orig_dump_entry(msg, portid, seq, bat_priv,
 566                                              if_outgoing, orig_node, sub)) {
 567                         rcu_read_unlock();
 568                         *idx_s = idx - 1;
 569                         return -EMSGSIZE;
 570                 }
 571         }
 572         rcu_read_unlock();
 573
 574         *idx_s = 0;
 575         *sub = 0;
 576         return 0;
 577 }
 578
 579 /**
 580  * batadv_v_orig_dump() - Dump the originators into a message
 581  * @msg: Netlink message to dump into
 582  * @cb: Control block containing additional options
 583  * @bat_priv: The bat priv with all the soft interface information
 584  * @if_outgoing: Limit dump to entries with this outgoing interface
 585  */
 586 static void
 587 batadv_v_orig_dump(struct sk_buff *msg, struct netlink_callback *cb,
 588                    struct batadv_priv *bat_priv,
 589                    struct batadv_hard_iface *if_outgoing)
 590 {
 591         struct batadv_hashtable *hash = bat_priv->orig_hash;
 592         struct hlist_head *head;
 593         int bucket = cb->args[0];
 594         int idx = cb->args[1];
 595         int sub = cb->args[2];
 596         int portid = NETLINK_CB(cb->skb).portid;
 597
 598         while (bucket < hash->size) {
 599                 head = &hash->table[bucket];
 600
 601                 if (batadv_v_orig_dump_bucket(msg, portid,
 602                                               cb->nlh->nlmsg_seq,
 603                                               bat_priv, if_outgoing, head, &idx,
 604                                               &sub))
 605                         break;
 606
 607                 bucket++;
 608         }
 609
 610         cb->args[0] = bucket;
 611         cb->args[1] = idx;
 612         cb->args[2] = sub;
 613 }
 614
 615 static int batadv_v_neigh_cmp(struct batadv_neigh_node *neigh1,
 616                               struct batadv_hard_iface *if_outgoing1,
 617                               struct batadv_neigh_node *neigh2,
 618                               struct batadv_hard_iface *if_outgoing2)
 619 {
 620         struct batadv_neigh_ifinfo *ifinfo1, *ifinfo2;
 621         int ret = 0;
 622
 623         ifinfo1 = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
 624         if (!ifinfo1)
 625                 goto err_ifinfo1;
 626
 627         ifinfo2 = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
 628         if (!ifinfo2)
 629                 goto err_ifinfo2;
 630
 631         ret = ifinfo1->bat_v.throughput - ifinfo2->bat_v.throughput;
 632
 633         batadv_neigh_ifinfo_put(ifinfo2);
 634 err_ifinfo2:
 635         batadv_neigh_ifinfo_put(ifinfo1);
 636 err_ifinfo1:
 637         return ret;
 638 }
 639
 640 static bool batadv_v_neigh_is_sob(struct batadv_neigh_node *neigh1,
 641                                   struct batadv_hard_iface *if_outgoing1,
 642                                   struct batadv_neigh_node *neigh2,
 643                                   struct batadv_hard_iface *if_outgoing2)
 644 {
 645         struct batadv_neigh_ifinfo *ifinfo1, *ifinfo2;
 646         u32 threshold;
 647         bool ret = false;
 648
 649         ifinfo1 = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
 650         if (!ifinfo1)
 651                 goto err_ifinfo1;
 652
 653         ifinfo2 = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
 654         if (!ifinfo2)
 655                 goto err_ifinfo2;
 656
 657         threshold = ifinfo1->bat_v.throughput / 4;
 658         threshold = ifinfo1->bat_v.throughput - threshold;
 659
 660         ret = ifinfo2->bat_v.throughput > threshold;
 661
 662         batadv_neigh_ifinfo_put(ifinfo2);
 663 err_ifinfo2:
 664         batadv_neigh_ifinfo_put(ifinfo1);
 665 err_ifinfo1:
 666         return ret;
 667 }
 668
 669 /**
 670  * batadv_v_init_sel_class() - initialize GW selection class
 671  * @bat_priv: the bat priv with all the soft interface information
 672  */
 673 static void batadv_v_init_sel_class(struct batadv_priv *bat_priv)
 674 {
 675         /* set default throughput difference threshold to 5Mbps */
 676         atomic_set(&bat_priv->gw.sel_class, 50);
 677 }
 678
 679 static ssize_t batadv_v_store_sel_class(struct batadv_priv *bat_priv,
 680                                         char *buff, size_t count)
 681 {
 682         u32 old_class, class;
 683
 684         if (!batadv_parse_throughput(bat_priv->soft_iface, buff,
 685                                      "B.A.T.M.A.N. V GW selection class",
 686                                      &class))
 687                 return -EINVAL;
 688
 689         old_class = atomic_read(&bat_priv->gw.sel_class);
 690         atomic_set(&bat_priv->gw.sel_class, class);
 691
 692         if (old_class != class)
 693                 batadv_gw_reselect(bat_priv);
 694
 695         return count;
 696 }
 697
 698 static ssize_t batadv_v_show_sel_class(struct batadv_priv *bat_priv, char *buff)
 699 {
 700         u32 class = atomic_read(&bat_priv->gw.sel_class);
 701
 702         return sprintf(buff, "%u.%u MBit\n", class / 10, class % 10);
 703 }
 704
 705 /**
 706  * batadv_v_gw_throughput_get() - retrieve the GW-bandwidth for a given GW
 707  * @gw_node: the GW to retrieve the metric for
 708  * @bw: the pointer where the metric will be stored. The metric is computed as
 709  *  the minimum between the GW advertised throughput and the path throughput to
 710  *  it in the mesh
 711  *
 712  * Return: 0 on success, -1 on failure
 713  */
 714 static int batadv_v_gw_throughput_get(struct batadv_gw_node *gw_node, u32 *bw)
 715 {
 716         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
 717         struct batadv_orig_node *orig_node;
 718         struct batadv_neigh_node *router;
 719         int ret = -1;
 720
 721         orig_node = gw_node->orig_node;
 722         router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
 723         if (!router)
 724                 goto out;
 725
 726         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
 727         if (!router_ifinfo)
 728                 goto out;
 729
 730         /* the GW metric is computed as the minimum between the path throughput
 731          * to reach the GW itself and the advertised bandwidth.
 732          * This gives us an approximation of the effective throughput that the
 733          * client can expect via this particular GW node
 734          */
 735         *bw = router_ifinfo->bat_v.throughput;
 736         *bw = min_t(u32, *bw, gw_node->bandwidth_down);
 737
 738         ret = 0;
 739 out:
 740         if (router)
 741                 batadv_neigh_node_put(router);
 742         if (router_ifinfo)
 743                 batadv_neigh_ifinfo_put(router_ifinfo);
 744
 745         return ret;
 746 }
 747
 748 /**
 749  * batadv_v_gw_get_best_gw_node() - retrieve the best GW node
 750  * @bat_priv: the bat priv with all the soft interface information
 751  *
 752  * Return: the GW node having the best GW-metric, NULL if no GW is known
 753  */
 754 static struct batadv_gw_node *
 755 batadv_v_gw_get_best_gw_node(struct batadv_priv *bat_priv)
 756 {
 757         struct batadv_gw_node *gw_node, *curr_gw = NULL;
 758         u32 max_bw = 0, bw;
 759
 760         rcu_read_lock();
 761         hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
 762                 if (!kref_get_unless_zero(&gw_node->refcount))
 763                         continue;
 764
 765                 if (batadv_v_gw_throughput_get(gw_node, &bw) < 0)
 766                         goto next;
 767
 768                 if (curr_gw && bw <= max_bw)
 769                         goto next;
 770
 771                 if (curr_gw)
 772                         batadv_gw_node_put(curr_gw);
 773
 774                 curr_gw = gw_node;
 775                 kref_get(&curr_gw->refcount);
 776                 max_bw = bw;
 777
 778 next:
 779                 batadv_gw_node_put(gw_node);
 780         }
 781         rcu_read_unlock();
 782
 783         return curr_gw;
 784 }
 785
 786 /**
 787  * batadv_v_gw_is_eligible() - check if a originator would be selected as GW
 788  * @bat_priv: the bat priv with all the soft interface information
 789  * @curr_gw_orig: originator representing the currently selected GW
 790  * @orig_node: the originator representing the new candidate
 791  *
 792  * Return: true if orig_node can be selected as current GW, false otherwise
 793  */
 794 static bool batadv_v_gw_is_eligible(struct batadv_priv *bat_priv,
 795                                     struct batadv_orig_node *curr_gw_orig,
 796                                     struct batadv_orig_node *orig_node)
 797 {
 798         struct batadv_gw_node *curr_gw, *orig_gw = NULL;
 799         u32 gw_throughput, orig_throughput, threshold;
 800         bool ret = false;
 801
 802         threshold = atomic_read(&bat_priv->gw.sel_class);
 803
 804         curr_gw = batadv_gw_node_get(bat_priv, curr_gw_orig);
 805         if (!curr_gw) {
 806                 ret = true;
 807                 goto out;
 808         }
 809
 810         if (batadv_v_gw_throughput_get(curr_gw, &gw_throughput) < 0) {
 811                 ret = true;
 812                 goto out;
 813         }
 814
 815         orig_gw = batadv_gw_node_get(bat_priv, orig_node);
 816         if (!orig_gw)
 817                 goto out;
 818
 819         if (batadv_v_gw_throughput_get(orig_gw, &orig_throughput) < 0)
 820                 goto out;
 821
 822         if (orig_throughput < gw_throughput)
 823                 goto out;
 824
 825         if ((orig_throughput - gw_throughput) < threshold)
 826                 goto out;
 827
 828         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 829                    "Restarting gateway selection: better gateway found (throughput curr: %u, throughput new: %u)\n",
 830                    gw_throughput, orig_throughput);
 831
 832         ret = true;
 833 out:
 834         if (curr_gw)
 835                 batadv_gw_node_put(curr_gw);
 836         if (orig_gw)
 837                 batadv_gw_node_put(orig_gw);
 838
 839         return ret;
 840 }
 841
 842 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
 843 /* fails if orig_node has no router */
 844 static int batadv_v_gw_write_buffer_text(struct batadv_priv *bat_priv,
 845                                          struct seq_file *seq,
 846                                          const struct batadv_gw_node *gw_node)
 847 {
 848         struct batadv_gw_node *curr_gw;
 849         struct batadv_neigh_node *router;
 850         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
 851         int ret = -1;
 852
 853         router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
 854         if (!router)
 855                 goto out;
 856
 857         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
 858         if (!router_ifinfo)
 859                 goto out;
 860
 861         curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
 862
 863         seq_printf(seq, "%s %pM (%9u.%1u) %pM [%10s]: %u.%u/%u.%u MBit\n",
 864                    (curr_gw == gw_node ? "=>" : "  "),
 865                    gw_node->orig_node->orig,
 866                    router_ifinfo->bat_v.throughput / 10,
 867                    router_ifinfo->bat_v.throughput % 10, router->addr,
 868                    router->if_incoming->net_dev->name,
 869                    gw_node->bandwidth_down / 10,
 870                    gw_node->bandwidth_down % 10,
 871                    gw_node->bandwidth_up / 10,
 872                    gw_node->bandwidth_up % 10);
 873         ret = seq_has_overflowed(seq) ? -1 : 0;
 874
 875         if (curr_gw)
 876                 batadv_gw_node_put(curr_gw);
 877 out:
 878         if (router_ifinfo)
 879                 batadv_neigh_ifinfo_put(router_ifinfo);
 880         if (router)
 881                 batadv_neigh_node_put(router);
 882         return ret;
 883 }
 884
 885 /**
 886  * batadv_v_gw_print() - print the gateway list
 887  * @bat_priv: the bat priv with all the soft interface information
 888  * @seq: gateway table seq_file struct
 889  */
 890 static void batadv_v_gw_print(struct batadv_priv *bat_priv,
 891                               struct seq_file *seq)
 892 {
 893         struct batadv_gw_node *gw_node;
 894         int gw_count = 0;
 895
 896         seq_puts(seq,
 897                  "      Gateway        ( throughput)           Nexthop [outgoingIF]: advertised uplink bandwidth\n");
 898
 899         rcu_read_lock();
 900         hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
 901                 /* fails if orig_node has no router */
 902                 if (batadv_v_gw_write_buffer_text(bat_priv, seq, gw_node) < 0)
 903                         continue;
 904
 905                 gw_count++;
 906         }
 907         rcu_read_unlock();
 908
 909         if (gw_count == 0)
 910                 seq_puts(seq, "No gateways in range ...\n");
 911 }
 912 #endif
 913
 914 /**
 915  * batadv_v_gw_dump_entry() - Dump a gateway into a message
 916  * @msg: Netlink message to dump into
 917  * @portid: Port making netlink request
 918  * @seq: Sequence number of netlink message
 919  * @bat_priv: The bat priv with all the soft interface information
 920  * @gw_node: Gateway to be dumped
 921  *
 922  * Return: Error code, or 0 on success
 923  */
 924 static int batadv_v_gw_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
 925                                   struct batadv_priv *bat_priv,
 926                                   struct batadv_gw_node *gw_node)
 927 {
 928         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
 929         struct batadv_neigh_node *router;
 930         struct batadv_gw_node *curr_gw;
 931         int ret = -EINVAL;
 932         void *hdr;
 933
 934         router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
 935         if (!router)
 936                 goto out;
 937
 938         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
 939         if (!router_ifinfo)
 940                 goto out;
 941
 942         curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
 943
 944         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
 945                           NLM_F_MULTI, BATADV_CMD_GET_GATEWAYS);
 946         if (!hdr) {
 947                 ret = -ENOBUFS;
 948                 goto out;
 949         }
 950
 951         ret = -EMSGSIZE;
 952
 953         if (curr_gw == gw_node) {
 954                 if (nla_put_flag(msg, BATADV_ATTR_FLAG_BEST)) {
 955                         genlmsg_cancel(msg, hdr);
 956                         goto out;
 957                 }
 958         }
 959
 960         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
 961                     gw_node->orig_node->orig)) {
 962                 genlmsg_cancel(msg, hdr);
 963                 goto out;
 964         }
 965
 966         if (nla_put_u32(msg, BATADV_ATTR_THROUGHPUT,
 967                         router_ifinfo->bat_v.throughput)) {
 968                 genlmsg_cancel(msg, hdr);
 969                 goto out;
 970         }
 971
 972         if (nla_put(msg, BATADV_ATTR_ROUTER, ETH_ALEN, router->addr)) {
 973                 genlmsg_cancel(msg, hdr);
 974                 goto out;
 975         }
 976
 977         if (nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
 978                            router->if_incoming->net_dev->name)) {
 979                 genlmsg_cancel(msg, hdr);
 980                 goto out;
 981         }
 982
 983         if (nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_DOWN,
 984                         gw_node->bandwidth_down)) {
 985                 genlmsg_cancel(msg, hdr);
 986                 goto out;
 987         }
 988
 989         if (nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_UP, gw_node->bandwidth_up)) {
 990                 genlmsg_cancel(msg, hdr);
 991                 goto out;
 992         }
 993
 994         genlmsg_end(msg, hdr);
 995         ret = 0;
 996
 997 out:
 998         if (router_ifinfo)
 999                 batadv_neigh_ifinfo_put(router_ifinfo);
1000         if (router)
1001                 batadv_neigh_node_put(router);
1002         return ret;
1003 }
1004
1005 /**
1006  * batadv_v_gw_dump() - Dump gateways into a message
1007  * @msg: Netlink message to dump into
1008  * @cb: Control block containing additional options
1009  * @bat_priv: The bat priv with all the soft interface information
1010  */
1011 static void batadv_v_gw_dump(struct sk_buff *msg, struct netlink_callback *cb,
1012                              struct batadv_priv *bat_priv)
1013 {
1014         int portid = NETLINK_CB(cb->skb).portid;
1015         struct batadv_gw_node *gw_node;
1016         int idx_skip = cb->args[0];
1017         int idx = 0;
1018
1019         rcu_read_lock();
1020         hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
1021                 if (idx++ < idx_skip)
1022                         continue;
1023
1024                 if (batadv_v_gw_dump_entry(msg, portid, cb->nlh->nlmsg_seq,
1025                                            bat_priv, gw_node)) {
1026                         idx_skip = idx - 1;
1027                         goto unlock;
1028                 }
1029         }
1030
1031         idx_skip = idx;
1032 unlock:
1033         rcu_read_unlock();
1034
1035         cb->args[0] = idx_skip;
1036 }
1037
1038 static struct batadv_algo_ops batadv_batman_v __read_mostly = {
1039         .name = "BATMAN_V",
1040         .iface = {
1041                 .activate = batadv_v_iface_activate,
1042                 .enable = batadv_v_iface_enable,
1043                 .disable = batadv_v_iface_disable,
1044                 .update_mac = batadv_v_iface_update_mac,
1045                 .primary_set = batadv_v_primary_iface_set,
1046         },
1047         .neigh = {
1048                 .hardif_init = batadv_v_hardif_neigh_init,
1049                 .cmp = batadv_v_neigh_cmp,
1050                 .is_similar_or_better = batadv_v_neigh_is_sob,
1051 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1052                 .print = batadv_v_neigh_print,
1053 #endif
1054                 .dump = batadv_v_neigh_dump,
1055         },
1056         .orig = {
1057 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1058                 .print = batadv_v_orig_print,
1059 #endif
1060                 .dump = batadv_v_orig_dump,
1061         },
1062         .gw = {
1063                 .init_sel_class = batadv_v_init_sel_class,
1064                 .store_sel_class = batadv_v_store_sel_class,
1065                 .show_sel_class = batadv_v_show_sel_class,
1066                 .get_best_gw_node = batadv_v_gw_get_best_gw_node,
1067                 .is_eligible = batadv_v_gw_is_eligible,
1068 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1069                 .print = batadv_v_gw_print,
1070 #endif
1071                 .dump = batadv_v_gw_dump,
1072         },
1073 };
1074
1075 /**
1076  * batadv_v_hardif_init() - initialize the algorithm specific fields in the
1077  *  hard-interface object
1078  * @hard_iface: the hard-interface to initialize
1079  */
1080 void batadv_v_hardif_init(struct batadv_hard_iface *hard_iface)
1081 {
1082         /* enable link throughput auto-detection by setting the throughput
1083          * override to zero
1084          */
1085         atomic_set(&hard_iface->bat_v.throughput_override, 0);
1086         atomic_set(&hard_iface->bat_v.elp_interval, 500);
1087 }
1088
1089 /**
1090  * batadv_v_mesh_init() - initialize the B.A.T.M.A.N. V private resources for a
1091  *  mesh
1092  * @bat_priv: the object representing the mesh interface to initialise
1093  *
1094  * Return: 0 on success or a negative error code otherwise
1095  */
1096 int batadv_v_mesh_init(struct batadv_priv *bat_priv)
1097 {
1098         int ret = 0;
1099
1100         ret = batadv_v_ogm_init(bat_priv);
1101         if (ret < 0)
1102                 return ret;
1103
1104         return 0;
1105 }
1106
1107 /**
1108  * batadv_v_mesh_free() - free the B.A.T.M.A.N. V private resources for a mesh
1109  * @bat_priv: the object representing the mesh interface to free
1110  */
1111 void batadv_v_mesh_free(struct batadv_priv *bat_priv)
1112 {
1113         batadv_v_ogm_free(bat_priv);
1114 }
1115
1116 /**
1117  * batadv_v_init() - B.A.T.M.A.N. V initialization function
1118  *
1119  * Description: Takes care of initializing all the subcomponents.
1120  * It is invoked upon module load only.
1121  *
1122  * Return: 0 on success or a negative error code otherwise
1123  */
1124 int __init batadv_v_init(void)
1125 {
1126         int ret;
1127
1128         /* B.A.T.M.A.N. V echo location protocol packet  */
1129         ret = batadv_recv_handler_register(BATADV_ELP,
1130                                            batadv_v_elp_packet_recv);
1131         if (ret < 0)
1132                 return ret;
1133
1134         ret = batadv_recv_handler_register(BATADV_OGM2,
1135                                            batadv_v_ogm_packet_recv);
1136         if (ret < 0)
1137                 goto elp_unregister;
1138
1139         ret = batadv_algo_register(&batadv_batman_v);
1140         if (ret < 0)
1141                 goto ogm_unregister;
1142
1143         return ret;
1144
1145 ogm_unregister:
1146         batadv_recv_handler_unregister(BATADV_OGM2);
1147
1148 elp_unregister:
1149         batadv_recv_handler_unregister(BATADV_ELP);
1150
1151         return ret;
1152 }