net/batman-adv/bat_v.c

   1 /* Copyright (C) 2013-2017  B.A.T.M.A.N. contributors:
   2  *
   3  * Linus Lüssing, Marek Lindner
   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_v.h"
  19 #include "main.h"
  20
  21 #include <linux/atomic.h>
  22 #include <linux/bug.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/batman_adv.h>
  41
  42 #include "bat_algo.h"
  43 #include "bat_v_elp.h"
  44 #include "bat_v_ogm.h"
  45 #include "gateway_client.h"
  46 #include "gateway_common.h"
  47 #include "hard-interface.h"
  48 #include "hash.h"
  49 #include "log.h"
  50 #include "netlink.h"
  51 #include "originator.h"
  52 #include "packet.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
 421  *  message
 422  * @msg: Netlink message to dump into
 423  * @portid: Port making netlink request
 424  * @seq: Sequence number of netlink message
 425  * @bat_priv: The bat priv with all the soft interface information
 426  * @if_outgoing: Limit dump to entries with this outgoing interface
 427  * @orig_node: Originator to dump
 428  * @neigh_node: Single hops neighbour
 429  * @best: Is the best originator
 430  *
 431  * Return: Error code, or 0 on success
 432  */
 433 static int
 434 batadv_v_orig_dump_subentry(struct sk_buff *msg, u32 portid, u32 seq,
 435                             struct batadv_priv *bat_priv,
 436                             struct batadv_hard_iface *if_outgoing,
 437                             struct batadv_orig_node *orig_node,
 438                             struct batadv_neigh_node *neigh_node,
 439                             bool best)
 440 {
 441         struct batadv_neigh_ifinfo *n_ifinfo;
 442         unsigned int last_seen_msecs;
 443         u32 throughput;
 444         void *hdr;
 445
 446         n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
 447         if (!n_ifinfo)
 448                 return 0;
 449
 450         throughput = n_ifinfo->bat_v.throughput * 100;
 451
 452         batadv_neigh_ifinfo_put(n_ifinfo);
 453
 454         last_seen_msecs = jiffies_to_msecs(jiffies - orig_node->last_seen);
 455
 456         if (if_outgoing != BATADV_IF_DEFAULT &&
 457             if_outgoing != neigh_node->if_incoming)
 458                 return 0;
 459
 460         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, NLM_F_MULTI,
 461                           BATADV_CMD_GET_ORIGINATORS);
 462         if (!hdr)
 463                 return -ENOBUFS;
 464
 465         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN, orig_node->orig) ||
 466             nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
 467                     neigh_node->addr) ||
 468             nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
 469                         neigh_node->if_incoming->net_dev->ifindex) ||
 470             nla_put_u32(msg, BATADV_ATTR_THROUGHPUT, throughput) ||
 471             nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
 472                         last_seen_msecs))
 473                 goto nla_put_failure;
 474
 475         if (best && nla_put_flag(msg, BATADV_ATTR_FLAG_BEST))
 476                 goto nla_put_failure;
 477
 478         genlmsg_end(msg, hdr);
 479         return 0;
 480
 481  nla_put_failure:
 482         genlmsg_cancel(msg, hdr);
 483         return -EMSGSIZE;
 484 }
 485
 486 /**
 487  * batadv_v_orig_dump_entry - Dump an originator entry into a message
 488  * @msg: Netlink message to dump into
 489  * @portid: Port making netlink request
 490  * @seq: Sequence number of netlink message
 491  * @bat_priv: The bat priv with all the soft interface information
 492  * @if_outgoing: Limit dump to entries with this outgoing interface
 493  * @orig_node: Originator to dump
 494  * @sub_s: Number of sub entries to skip
 495  *
 496  * This function assumes the caller holds rcu_read_lock().
 497  *
 498  * Return: Error code, or 0 on success
 499  */
 500 static int
 501 batadv_v_orig_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
 502                          struct batadv_priv *bat_priv,
 503                          struct batadv_hard_iface *if_outgoing,
 504                          struct batadv_orig_node *orig_node, int *sub_s)
 505 {
 506         struct batadv_neigh_node *neigh_node_best;
 507         struct batadv_neigh_node *neigh_node;
 508         int sub = 0;
 509         bool best;
 510
 511         neigh_node_best = batadv_orig_router_get(orig_node, if_outgoing);
 512         if (!neigh_node_best)
 513                 goto out;
 514
 515         hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
 516                 if (sub++ < *sub_s)
 517                         continue;
 518
 519                 best = (neigh_node == neigh_node_best);
 520
 521                 if (batadv_v_orig_dump_subentry(msg, portid, seq, bat_priv,
 522                                                 if_outgoing, orig_node,
 523                                                 neigh_node, best)) {
 524                         batadv_neigh_node_put(neigh_node_best);
 525
 526                         *sub_s = sub - 1;
 527                         return -EMSGSIZE;
 528                 }
 529         }
 530
 531  out:
 532         if (neigh_node_best)
 533                 batadv_neigh_node_put(neigh_node_best);
 534
 535         *sub_s = 0;
 536         return 0;
 537 }
 538
 539 /**
 540  * batadv_v_orig_dump_bucket - Dump an originator bucket into a
 541  *  message
 542  * @msg: Netlink message to dump into
 543  * @portid: Port making netlink request
 544  * @seq: Sequence number of netlink message
 545  * @bat_priv: The bat priv with all the soft interface information
 546  * @if_outgoing: Limit dump to entries with this outgoing interface
 547  * @head: Bucket to be dumped
 548  * @idx_s: Number of entries to be skipped
 549  * @sub: Number of sub entries to be skipped
 550  *
 551  * Return: Error code, or 0 on success
 552  */
 553 static int
 554 batadv_v_orig_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
 555                           struct batadv_priv *bat_priv,
 556                           struct batadv_hard_iface *if_outgoing,
 557                           struct hlist_head *head, int *idx_s, int *sub)
 558 {
 559         struct batadv_orig_node *orig_node;
 560         int idx = 0;
 561
 562         rcu_read_lock();
 563         hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
 564                 if (idx++ < *idx_s)
 565                         continue;
 566
 567                 if (batadv_v_orig_dump_entry(msg, portid, seq, bat_priv,
 568                                              if_outgoing, orig_node, sub)) {
 569                         rcu_read_unlock();
 570                         *idx_s = idx - 1;
 571                         return -EMSGSIZE;
 572                 }
 573         }
 574         rcu_read_unlock();
 575
 576         *idx_s = 0;
 577         *sub = 0;
 578         return 0;
 579 }
 580
 581 /**
 582  * batadv_v_orig_dump - Dump the originators into a message
 583  * @msg: Netlink message to dump into
 584  * @cb: Control block containing additional options
 585  * @bat_priv: The bat priv with all the soft interface information
 586  * @if_outgoing: Limit dump to entries with this outgoing interface
 587  */
 588 static void
 589 batadv_v_orig_dump(struct sk_buff *msg, struct netlink_callback *cb,
 590                    struct batadv_priv *bat_priv,
 591                    struct batadv_hard_iface *if_outgoing)
 592 {
 593         struct batadv_hashtable *hash = bat_priv->orig_hash;
 594         struct hlist_head *head;
 595         int bucket = cb->args[0];
 596         int idx = cb->args[1];
 597         int sub = cb->args[2];
 598         int portid = NETLINK_CB(cb->skb).portid;
 599
 600         while (bucket < hash->size) {
 601                 head = &hash->table[bucket];
 602
 603                 if (batadv_v_orig_dump_bucket(msg, portid,
 604                                               cb->nlh->nlmsg_seq,
 605                                               bat_priv, if_outgoing, head, &idx,
 606                                               &sub))
 607                         break;
 608
 609                 bucket++;
 610         }
 611
 612         cb->args[0] = bucket;
 613         cb->args[1] = idx;
 614         cb->args[2] = sub;
 615 }
 616
 617 static int batadv_v_neigh_cmp(struct batadv_neigh_node *neigh1,
 618                               struct batadv_hard_iface *if_outgoing1,
 619                               struct batadv_neigh_node *neigh2,
 620                               struct batadv_hard_iface *if_outgoing2)
 621 {
 622         struct batadv_neigh_ifinfo *ifinfo1, *ifinfo2;
 623         int ret = 0;
 624
 625         ifinfo1 = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
 626         if (WARN_ON(!ifinfo1))
 627                 goto err_ifinfo1;
 628
 629         ifinfo2 = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
 630         if (WARN_ON(!ifinfo2))
 631                 goto err_ifinfo2;
 632
 633         ret = ifinfo1->bat_v.throughput - ifinfo2->bat_v.throughput;
 634
 635         batadv_neigh_ifinfo_put(ifinfo2);
 636 err_ifinfo2:
 637         batadv_neigh_ifinfo_put(ifinfo1);
 638 err_ifinfo1:
 639         return ret;
 640 }
 641
 642 static bool batadv_v_neigh_is_sob(struct batadv_neigh_node *neigh1,
 643                                   struct batadv_hard_iface *if_outgoing1,
 644                                   struct batadv_neigh_node *neigh2,
 645                                   struct batadv_hard_iface *if_outgoing2)
 646 {
 647         struct batadv_neigh_ifinfo *ifinfo1, *ifinfo2;
 648         u32 threshold;
 649         bool ret = false;
 650
 651         ifinfo1 = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
 652         if (WARN_ON(!ifinfo1))
 653                 goto err_ifinfo1;
 654
 655         ifinfo2 = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
 656         if (WARN_ON(!ifinfo2))
 657                 goto err_ifinfo2;
 658
 659         threshold = ifinfo1->bat_v.throughput / 4;
 660         threshold = ifinfo1->bat_v.throughput - threshold;
 661
 662         ret = ifinfo2->bat_v.throughput > threshold;
 663
 664         batadv_neigh_ifinfo_put(ifinfo2);
 665 err_ifinfo2:
 666         batadv_neigh_ifinfo_put(ifinfo1);
 667 err_ifinfo1:
 668         return ret;
 669 }
 670
 671 /**
 672  * batadv_v_init_sel_class - initialize GW selection class
 673  * @bat_priv: the bat priv with all the soft interface information
 674  */
 675 static void batadv_v_init_sel_class(struct batadv_priv *bat_priv)
 676 {
 677         /* set default throughput difference threshold to 5Mbps */
 678         atomic_set(&bat_priv->gw.sel_class, 50);
 679 }
 680
 681 static ssize_t batadv_v_store_sel_class(struct batadv_priv *bat_priv,
 682                                         char *buff, size_t count)
 683 {
 684         u32 old_class, class;
 685
 686         if (!batadv_parse_throughput(bat_priv->soft_iface, buff,
 687                                      "B.A.T.M.A.N. V GW selection class",
 688                                      &class))
 689                 return -EINVAL;
 690
 691         old_class = atomic_read(&bat_priv->gw.sel_class);
 692         atomic_set(&bat_priv->gw.sel_class, class);
 693
 694         if (old_class != class)
 695                 batadv_gw_reselect(bat_priv);
 696
 697         return count;
 698 }
 699
 700 static ssize_t batadv_v_show_sel_class(struct batadv_priv *bat_priv, char *buff)
 701 {
 702         u32 class = atomic_read(&bat_priv->gw.sel_class);
 703
 704         return sprintf(buff, "%u.%u MBit\n", class / 10, class % 10);
 705 }
 706
 707 /**
 708  * batadv_v_gw_throughput_get - retrieve the GW-bandwidth for a given GW
 709  * @gw_node: the GW to retrieve the metric for
 710  * @bw: the pointer where the metric will be stored. The metric is computed as
 711  *  the minimum between the GW advertised throughput and the path throughput to
 712  *  it in the mesh
 713  *
 714  * Return: 0 on success, -1 on failure
 715  */
 716 static int batadv_v_gw_throughput_get(struct batadv_gw_node *gw_node, u32 *bw)
 717 {
 718         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
 719         struct batadv_orig_node *orig_node;
 720         struct batadv_neigh_node *router;
 721         int ret = -1;
 722
 723         orig_node = gw_node->orig_node;
 724         router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
 725         if (!router)
 726                 goto out;
 727
 728         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
 729         if (!router_ifinfo)
 730                 goto out;
 731
 732         /* the GW metric is computed as the minimum between the path throughput
 733          * to reach the GW itself and the advertised bandwidth.
 734          * This gives us an approximation of the effective throughput that the
 735          * client can expect via this particular GW node
 736          */
 737         *bw = router_ifinfo->bat_v.throughput;
 738         *bw = min_t(u32, *bw, gw_node->bandwidth_down);
 739
 740         ret = 0;
 741 out:
 742         if (router)
 743                 batadv_neigh_node_put(router);
 744         if (router_ifinfo)
 745                 batadv_neigh_ifinfo_put(router_ifinfo);
 746
 747         return ret;
 748 }
 749
 750 /**
 751  * batadv_v_gw_get_best_gw_node - retrieve the best GW node
 752  * @bat_priv: the bat priv with all the soft interface information
 753  *
 754  * Return: the GW node having the best GW-metric, NULL if no GW is known
 755  */
 756 static struct batadv_gw_node *
 757 batadv_v_gw_get_best_gw_node(struct batadv_priv *bat_priv)
 758 {
 759         struct batadv_gw_node *gw_node, *curr_gw = NULL;
 760         u32 max_bw = 0, bw;
 761
 762         rcu_read_lock();
 763         hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
 764                 if (!kref_get_unless_zero(&gw_node->refcount))
 765                         continue;
 766
 767                 if (batadv_v_gw_throughput_get(gw_node, &bw) < 0)
 768                         goto next;
 769
 770                 if (curr_gw && (bw <= max_bw))
 771                         goto next;
 772
 773                 if (curr_gw)
 774                         batadv_gw_node_put(curr_gw);
 775
 776                 curr_gw = gw_node;
 777                 kref_get(&curr_gw->refcount);
 778                 max_bw = bw;
 779
 780 next:
 781                 batadv_gw_node_put(gw_node);
 782         }
 783         rcu_read_unlock();
 784
 785         return curr_gw;
 786 }
 787
 788 /**
 789  * batadv_v_gw_is_eligible - check if a originator would be selected as GW
 790  * @bat_priv: the bat priv with all the soft interface information
 791  * @curr_gw_orig: originator representing the currently selected GW
 792  * @orig_node: the originator representing the new candidate
 793  *
 794  * Return: true if orig_node can be selected as current GW, false otherwise
 795  */
 796 static bool batadv_v_gw_is_eligible(struct batadv_priv *bat_priv,
 797                                     struct batadv_orig_node *curr_gw_orig,
 798                                     struct batadv_orig_node *orig_node)
 799 {
 800         struct batadv_gw_node *curr_gw, *orig_gw = NULL;
 801         u32 gw_throughput, orig_throughput, threshold;
 802         bool ret = false;
 803
 804         threshold = atomic_read(&bat_priv->gw.sel_class);
 805
 806         curr_gw = batadv_gw_node_get(bat_priv, curr_gw_orig);
 807         if (!curr_gw) {
 808                 ret = true;
 809                 goto out;
 810         }
 811
 812         if (batadv_v_gw_throughput_get(curr_gw, &gw_throughput) < 0) {
 813                 ret = true;
 814                 goto out;
 815         }
 816
 817         orig_gw = batadv_gw_node_get(bat_priv, orig_node);
 818         if (!orig_node)
 819                 goto out;
 820
 821         if (batadv_v_gw_throughput_get(orig_gw, &orig_throughput) < 0)
 822                 goto out;
 823
 824         if (orig_throughput < gw_throughput)
 825                 goto out;
 826
 827         if ((orig_throughput - gw_throughput) < threshold)
 828                 goto out;
 829
 830         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 831                    "Restarting gateway selection: better gateway found (throughput curr: %u, throughput new: %u)\n",
 832                    gw_throughput, orig_throughput);
 833
 834         ret = true;
 835 out:
 836         if (curr_gw)
 837                 batadv_gw_node_put(curr_gw);
 838         if (orig_gw)
 839                 batadv_gw_node_put(orig_gw);
 840
 841         return ret;
 842 }
 843
 844 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
 845 /* fails if orig_node has no router */
 846 static int batadv_v_gw_write_buffer_text(struct batadv_priv *bat_priv,
 847                                          struct seq_file *seq,
 848                                          const struct batadv_gw_node *gw_node)
 849 {
 850         struct batadv_gw_node *curr_gw;
 851         struct batadv_neigh_node *router;
 852         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
 853         int ret = -1;
 854
 855         router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
 856         if (!router)
 857                 goto out;
 858
 859         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
 860         if (!router_ifinfo)
 861                 goto out;
 862
 863         curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
 864
 865         seq_printf(seq, "%s %pM (%9u.%1u) %pM [%10s]: %u.%u/%u.%u MBit\n",
 866                    (curr_gw == gw_node ? "=>" : "  "),
 867                    gw_node->orig_node->orig,
 868                    router_ifinfo->bat_v.throughput / 10,
 869                    router_ifinfo->bat_v.throughput % 10, router->addr,
 870                    router->if_incoming->net_dev->name,
 871                    gw_node->bandwidth_down / 10,
 872                    gw_node->bandwidth_down % 10,
 873                    gw_node->bandwidth_up / 10,
 874                    gw_node->bandwidth_up % 10);
 875         ret = seq_has_overflowed(seq) ? -1 : 0;
 876
 877         if (curr_gw)
 878                 batadv_gw_node_put(curr_gw);
 879 out:
 880         if (router_ifinfo)
 881                 batadv_neigh_ifinfo_put(router_ifinfo);
 882         if (router)
 883                 batadv_neigh_node_put(router);
 884         return ret;
 885 }
 886
 887 /**
 888  * batadv_v_gw_print - print the gateway list
 889  * @bat_priv: the bat priv with all the soft interface information
 890  * @seq: gateway table seq_file struct
 891  */
 892 static void batadv_v_gw_print(struct batadv_priv *bat_priv,
 893                               struct seq_file *seq)
 894 {
 895         struct batadv_gw_node *gw_node;
 896         int gw_count = 0;
 897
 898         seq_puts(seq,
 899                  "      Gateway        ( throughput)           Nexthop [outgoingIF]: advertised uplink bandwidth\n");
 900
 901         rcu_read_lock();
 902         hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
 903                 /* fails if orig_node has no router */
 904                 if (batadv_v_gw_write_buffer_text(bat_priv, seq, gw_node) < 0)
 905                         continue;
 906
 907                 gw_count++;
 908         }
 909         rcu_read_unlock();
 910
 911         if (gw_count == 0)
 912                 seq_puts(seq, "No gateways in range ...\n");
 913 }
 914 #endif
 915
 916 /**
 917  * batadv_v_gw_dump_entry - Dump a gateway into a message
 918  * @msg: Netlink message to dump into
 919  * @portid: Port making netlink request
 920  * @seq: Sequence number of netlink message
 921  * @bat_priv: The bat priv with all the soft interface information
 922  * @gw_node: Gateway to be dumped
 923  *
 924  * Return: Error code, or 0 on success
 925  */
 926 static int batadv_v_gw_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
 927                                   struct batadv_priv *bat_priv,
 928                                   struct batadv_gw_node *gw_node)
 929 {
 930         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
 931         struct batadv_neigh_node *router;
 932         struct batadv_gw_node *curr_gw;
 933         int ret = -EINVAL;
 934         void *hdr;
 935
 936         router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
 937         if (!router)
 938                 goto out;
 939
 940         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
 941         if (!router_ifinfo)
 942                 goto out;
 943
 944         curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
 945
 946         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
 947                           NLM_F_MULTI, BATADV_CMD_GET_GATEWAYS);
 948         if (!hdr) {
 949                 ret = -ENOBUFS;
 950                 goto out;
 951         }
 952
 953         ret = -EMSGSIZE;
 954
 955         if (curr_gw == gw_node) {
 956                 if (nla_put_flag(msg, BATADV_ATTR_FLAG_BEST)) {
 957                         genlmsg_cancel(msg, hdr);
 958                         goto out;
 959                 }
 960         }
 961
 962         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
 963                     gw_node->orig_node->orig)) {
 964                 genlmsg_cancel(msg, hdr);
 965                 goto out;
 966         }
 967
 968         if (nla_put_u32(msg, BATADV_ATTR_THROUGHPUT,
 969                         router_ifinfo->bat_v.throughput)) {
 970                 genlmsg_cancel(msg, hdr);
 971                 goto out;
 972         }
 973
 974         if (nla_put(msg, BATADV_ATTR_ROUTER, ETH_ALEN, router->addr)) {
 975                 genlmsg_cancel(msg, hdr);
 976                 goto out;
 977         }
 978
 979         if (nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
 980                            router->if_incoming->net_dev->name)) {
 981                 genlmsg_cancel(msg, hdr);
 982                 goto out;
 983         }
 984
 985         if (nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_DOWN,
 986                         gw_node->bandwidth_down)) {
 987                 genlmsg_cancel(msg, hdr);
 988                 goto out;
 989         }
 990
 991         if (nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_UP, gw_node->bandwidth_up)) {
 992                 genlmsg_cancel(msg, hdr);
 993                 goto out;
 994         }
 995
 996         genlmsg_end(msg, hdr);
 997         ret = 0;
 998
 999 out:
1000         if (router_ifinfo)
1001                 batadv_neigh_ifinfo_put(router_ifinfo);
1002         if (router)
1003                 batadv_neigh_node_put(router);
1004         return ret;
1005 }
1006
1007 /**
1008  * batadv_v_gw_dump - Dump gateways into a message
1009  * @msg: Netlink message to dump into
1010  * @cb: Control block containing additional options
1011  * @bat_priv: The bat priv with all the soft interface information
1012  */
1013 static void batadv_v_gw_dump(struct sk_buff *msg, struct netlink_callback *cb,
1014                              struct batadv_priv *bat_priv)
1015 {
1016         int portid = NETLINK_CB(cb->skb).portid;
1017         struct batadv_gw_node *gw_node;
1018         int idx_skip = cb->args[0];
1019         int idx = 0;
1020
1021         rcu_read_lock();
1022         hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
1023                 if (idx++ < idx_skip)
1024                         continue;
1025
1026                 if (batadv_v_gw_dump_entry(msg, portid, cb->nlh->nlmsg_seq,
1027                                            bat_priv, gw_node)) {
1028                         idx_skip = idx - 1;
1029                         goto unlock;
1030                 }
1031         }
1032
1033         idx_skip = idx;
1034 unlock:
1035         rcu_read_unlock();
1036
1037         cb->args[0] = idx_skip;
1038 }
1039
1040 static struct batadv_algo_ops batadv_batman_v __read_mostly = {
1041         .name = "BATMAN_V",
1042         .iface = {
1043                 .activate = batadv_v_iface_activate,
1044                 .enable = batadv_v_iface_enable,
1045                 .disable = batadv_v_iface_disable,
1046                 .update_mac = batadv_v_iface_update_mac,
1047                 .primary_set = batadv_v_primary_iface_set,
1048         },
1049         .neigh = {
1050                 .hardif_init = batadv_v_hardif_neigh_init,
1051                 .cmp = batadv_v_neigh_cmp,
1052                 .is_similar_or_better = batadv_v_neigh_is_sob,
1053 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1054                 .print = batadv_v_neigh_print,
1055 #endif
1056                 .dump = batadv_v_neigh_dump,
1057         },
1058         .orig = {
1059 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1060                 .print = batadv_v_orig_print,
1061 #endif
1062                 .dump = batadv_v_orig_dump,
1063         },
1064         .gw = {
1065                 .init_sel_class = batadv_v_init_sel_class,
1066                 .store_sel_class = batadv_v_store_sel_class,
1067                 .show_sel_class = batadv_v_show_sel_class,
1068                 .get_best_gw_node = batadv_v_gw_get_best_gw_node,
1069                 .is_eligible = batadv_v_gw_is_eligible,
1070 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1071                 .print = batadv_v_gw_print,
1072 #endif
1073                 .dump = batadv_v_gw_dump,
1074         },
1075 };
1076
1077 /**
1078  * batadv_v_hardif_init - initialize the algorithm specific fields in the
1079  *  hard-interface object
1080  * @hard_iface: the hard-interface to initialize
1081  */
1082 void batadv_v_hardif_init(struct batadv_hard_iface *hard_iface)
1083 {
1084         /* enable link throughput auto-detection by setting the throughput
1085          * override to zero
1086          */
1087         atomic_set(&hard_iface->bat_v.throughput_override, 0);
1088         atomic_set(&hard_iface->bat_v.elp_interval, 500);
1089 }
1090
1091 /**
1092  * batadv_v_mesh_init - initialize the B.A.T.M.A.N. V private resources for a
1093  *  mesh
1094  * @bat_priv: the object representing the mesh interface to initialise
1095  *
1096  * Return: 0 on success or a negative error code otherwise
1097  */
1098 int batadv_v_mesh_init(struct batadv_priv *bat_priv)
1099 {
1100         int ret = 0;
1101
1102         ret = batadv_v_ogm_init(bat_priv);
1103         if (ret < 0)
1104                 return ret;
1105
1106         return 0;
1107 }
1108
1109 /**
1110  * batadv_v_mesh_free - free the B.A.T.M.A.N. V private resources for a mesh
1111  * @bat_priv: the object representing the mesh interface to free
1112  */
1113 void batadv_v_mesh_free(struct batadv_priv *bat_priv)
1114 {
1115         batadv_v_ogm_free(bat_priv);
1116 }
1117
1118 /**
1119  * batadv_v_init - B.A.T.M.A.N. V initialization function
1120  *
1121  * Description: Takes care of initializing all the subcomponents.
1122  * It is invoked upon module load only.
1123  *
1124  * Return: 0 on success or a negative error code otherwise
1125  */
1126 int __init batadv_v_init(void)
1127 {
1128         int ret;
1129
1130         /* B.A.T.M.A.N. V echo location protocol packet  */
1131         ret = batadv_recv_handler_register(BATADV_ELP,
1132                                            batadv_v_elp_packet_recv);
1133         if (ret < 0)
1134                 return ret;
1135
1136         ret = batadv_recv_handler_register(BATADV_OGM2,
1137                                            batadv_v_ogm_packet_recv);
1138         if (ret < 0)
1139                 goto elp_unregister;
1140
1141         ret = batadv_algo_register(&batadv_batman_v);
1142         if (ret < 0)
1143                 goto ogm_unregister;
1144
1145         return ret;
1146
1147 ogm_unregister:
1148         batadv_recv_handler_unregister(BATADV_OGM2);
1149
1150 elp_unregister:
1151         batadv_recv_handler_unregister(BATADV_ELP);
1152
1153         return ret;
1154 }