net/batman-adv/soft-interface.c

   1 /* Copyright (C) 2007-2012 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, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  17  * 02110-1301, USA
  18  */
  19
  20 #include "main.h"
  21 #include "soft-interface.h"
  22 #include "hard-interface.h"
  23 #include "routing.h"
  24 #include "send.h"
  25 #include "debugfs.h"
  26 #include "translation-table.h"
  27 #include "hash.h"
  28 #include "gateway_common.h"
  29 #include "gateway_client.h"
  30 #include "sysfs.h"
  31 #include "originator.h"
  32 #include <linux/slab.h>
  33 #include <linux/ethtool.h>
  34 #include <linux/etherdevice.h>
  35 #include <linux/if_vlan.h>
  36 #include "unicast.h"
  37 #include "bridge_loop_avoidance.h"
  38
  39
  40 static int batadv_get_settings(struct net_device *dev, struct ethtool_cmd *cmd);
  41 static void batadv_get_drvinfo(struct net_device *dev,
  42                                struct ethtool_drvinfo *info);
  43 static u32 batadv_get_msglevel(struct net_device *dev);
  44 static void batadv_set_msglevel(struct net_device *dev, u32 value);
  45 static u32 batadv_get_link(struct net_device *dev);
  46 static void batadv_get_strings(struct net_device *dev, u32 stringset, u8 *data);
  47 static void batadv_get_ethtool_stats(struct net_device *dev,
  48                                      struct ethtool_stats *stats, u64 *data);
  49 static int batadv_get_sset_count(struct net_device *dev, int stringset);
  50
  51 static const struct ethtool_ops batadv_ethtool_ops = {
  52         .get_settings = batadv_get_settings,
  53         .get_drvinfo = batadv_get_drvinfo,
  54         .get_msglevel = batadv_get_msglevel,
  55         .set_msglevel = batadv_set_msglevel,
  56         .get_link = batadv_get_link,
  57         .get_strings = batadv_get_strings,
  58         .get_ethtool_stats = batadv_get_ethtool_stats,
  59         .get_sset_count = batadv_get_sset_count,
  60 };
  61
  62 int batadv_skb_head_push(struct sk_buff *skb, unsigned int len)
  63 {
  64         int result;
  65
  66         /* TODO: We must check if we can release all references to non-payload
  67          * data using skb_header_release in our skbs to allow skb_cow_header to
  68          * work optimally. This means that those skbs are not allowed to read
  69          * or write any data which is before the current position of skb->data
  70          * after that call and thus allow other skbs with the same data buffer
  71          * to write freely in that area.
  72          */
  73         result = skb_cow_head(skb, len);
  74         if (result < 0)
  75                 return result;
  76
  77         skb_push(skb, len);
  78         return 0;
  79 }
  80
  81 static int batadv_interface_open(struct net_device *dev)
  82 {
  83         netif_start_queue(dev);
  84         return 0;
  85 }
  86
  87 static int batadv_interface_release(struct net_device *dev)
  88 {
  89         netif_stop_queue(dev);
  90         return 0;
  91 }
  92
  93 static struct net_device_stats *batadv_interface_stats(struct net_device *dev)
  94 {
  95         struct batadv_priv *bat_priv = netdev_priv(dev);
  96         return &bat_priv->stats;
  97 }
  98
  99 static int batadv_interface_set_mac_addr(struct net_device *dev, void *p)
 100 {
 101         struct batadv_priv *bat_priv = netdev_priv(dev);
 102         struct sockaddr *addr = p;
 103         uint8_t old_addr[ETH_ALEN];
 104
 105         if (!is_valid_ether_addr(addr->sa_data))
 106                 return -EADDRNOTAVAIL;
 107
 108         memcpy(old_addr, dev->dev_addr, ETH_ALEN);
 109         memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
 110
 111         /* only modify transtable if it has been initialized before */
 112         if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE) {
 113                 batadv_tt_local_remove(bat_priv, old_addr,
 114                                        "mac address changed", false);
 115                 batadv_tt_local_add(dev, addr->sa_data, BATADV_NULL_IFINDEX);
 116         }
 117
 118         dev->addr_assign_type &= ~NET_ADDR_RANDOM;
 119         return 0;
 120 }
 121
 122 static int batadv_interface_change_mtu(struct net_device *dev, int new_mtu)
 123 {
 124         /* check ranges */
 125         if ((new_mtu < 68) || (new_mtu > batadv_hardif_min_mtu(dev)))
 126                 return -EINVAL;
 127
 128         dev->mtu = new_mtu;
 129
 130         return 0;
 131 }
 132
 133 static int batadv_interface_tx(struct sk_buff *skb,
 134                                struct net_device *soft_iface)
 135 {
 136         struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
 137         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 138         struct batadv_hard_iface *primary_if = NULL;
 139         struct batadv_bcast_packet *bcast_packet;
 140         struct vlan_ethhdr *vhdr;
 141         __be16 ethertype = __constant_htons(BATADV_ETH_P_BATMAN);
 142         static const uint8_t stp_addr[ETH_ALEN] = {0x01, 0x80, 0xC2, 0x00, 0x00,
 143                                                    0x00};
 144         unsigned int header_len = 0;
 145         int data_len = skb->len, ret;
 146         short vid __maybe_unused = -1;
 147         bool do_bcast = false;
 148
 149         if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
 150                 goto dropped;
 151
 152         soft_iface->trans_start = jiffies;
 153
 154         switch (ntohs(ethhdr->h_proto)) {
 155         case ETH_P_8021Q:
 156                 vhdr = (struct vlan_ethhdr *)skb->data;
 157                 vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;
 158
 159                 if (vhdr->h_vlan_encapsulated_proto != ethertype)
 160                         break;
 161
 162                 /* fall through */
 163         case BATADV_ETH_P_BATMAN:
 164                 goto dropped;
 165         }
 166
 167         if (batadv_bla_tx(bat_priv, skb, vid))
 168                 goto dropped;
 169
 170         /* Register the client MAC in the transtable */
 171         batadv_tt_local_add(soft_iface, ethhdr->h_source, skb->skb_iif);
 172
 173         /* don't accept stp packets. STP does not help in meshes.
 174          * better use the bridge loop avoidance ...
 175          */
 176         if (batadv_compare_eth(ethhdr->h_dest, stp_addr))
 177                 goto dropped;
 178
 179         if (is_multicast_ether_addr(ethhdr->h_dest)) {
 180                 do_bcast = true;
 181
 182                 switch (atomic_read(&bat_priv->gw_mode)) {
 183                 case BATADV_GW_MODE_SERVER:
 184                         /* gateway servers should not send dhcp
 185                          * requests into the mesh
 186                          */
 187                         ret = batadv_gw_is_dhcp_target(skb, &header_len);
 188                         if (ret)
 189                                 goto dropped;
 190                         break;
 191                 case BATADV_GW_MODE_CLIENT:
 192                         /* gateway clients should send dhcp requests
 193                          * via unicast to their gateway
 194                          */
 195                         ret = batadv_gw_is_dhcp_target(skb, &header_len);
 196                         if (ret)
 197                                 do_bcast = false;
 198                         break;
 199                 case BATADV_GW_MODE_OFF:
 200                 default:
 201                         break;
 202                 }
 203         }
 204
 205         /* ethernet packet should be broadcasted */
 206         if (do_bcast) {
 207                 primary_if = batadv_primary_if_get_selected(bat_priv);
 208                 if (!primary_if)
 209                         goto dropped;
 210
 211                 if (batadv_skb_head_push(skb, sizeof(*bcast_packet)) < 0)
 212                         goto dropped;
 213
 214                 bcast_packet = (struct batadv_bcast_packet *)skb->data;
 215                 bcast_packet->header.version = BATADV_COMPAT_VERSION;
 216                 bcast_packet->header.ttl = BATADV_TTL;
 217
 218                 /* batman packet type: broadcast */
 219                 bcast_packet->header.packet_type = BATADV_BCAST;
 220                 bcast_packet->reserved = 0;
 221
 222                 /* hw address of first interface is the orig mac because only
 223                  * this mac is known throughout the mesh
 224                  */
 225                 memcpy(bcast_packet->orig,
 226                        primary_if->net_dev->dev_addr, ETH_ALEN);
 227
 228                 /* set broadcast sequence number */
 229                 bcast_packet->seqno =
 230                         htonl(atomic_inc_return(&bat_priv->bcast_seqno));
 231
 232                 batadv_add_bcast_packet_to_list(bat_priv, skb, 1);
 233
 234                 /* a copy is stored in the bcast list, therefore removing
 235                  * the original skb.
 236                  */
 237                 kfree_skb(skb);
 238
 239         /* unicast packet */
 240         } else {
 241                 if (atomic_read(&bat_priv->gw_mode) != BATADV_GW_MODE_OFF) {
 242                         ret = batadv_gw_out_of_range(bat_priv, skb, ethhdr);
 243                         if (ret)
 244                                 goto dropped;
 245                 }
 246
 247                 ret = batadv_unicast_send_skb(skb, bat_priv);
 248                 if (ret != 0)
 249                         goto dropped_freed;
 250         }
 251
 252         bat_priv->stats.tx_packets++;
 253         bat_priv->stats.tx_bytes += data_len;
 254         goto end;
 255
 256 dropped:
 257         kfree_skb(skb);
 258 dropped_freed:
 259         bat_priv->stats.tx_dropped++;
 260 end:
 261         if (primary_if)
 262                 batadv_hardif_free_ref(primary_if);
 263         return NETDEV_TX_OK;
 264 }
 265
 266 void batadv_interface_rx(struct net_device *soft_iface,
 267                          struct sk_buff *skb, struct batadv_hard_iface *recv_if,
 268                          int hdr_size)
 269 {
 270         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 271         struct ethhdr *ethhdr;
 272         struct vlan_ethhdr *vhdr;
 273         struct batadv_header *batadv_header = (struct batadv_header *)skb->data;
 274         short vid __maybe_unused = -1;
 275         __be16 ethertype = __constant_htons(BATADV_ETH_P_BATMAN);
 276         bool is_bcast;
 277
 278         is_bcast = (batadv_header->packet_type == BATADV_BCAST);
 279
 280         /* check if enough space is available for pulling, and pull */
 281         if (!pskb_may_pull(skb, hdr_size))
 282                 goto dropped;
 283
 284         skb_pull_rcsum(skb, hdr_size);
 285         skb_reset_mac_header(skb);
 286
 287         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 288
 289         switch (ntohs(ethhdr->h_proto)) {
 290         case ETH_P_8021Q:
 291                 vhdr = (struct vlan_ethhdr *)skb->data;
 292                 vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;
 293
 294                 if (vhdr->h_vlan_encapsulated_proto != ethertype)
 295                         break;
 296
 297                 /* fall through */
 298         case BATADV_ETH_P_BATMAN:
 299                 goto dropped;
 300         }
 301
 302         /* skb->dev & skb->pkt_type are set here */
 303         if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
 304                 goto dropped;
 305         skb->protocol = eth_type_trans(skb, soft_iface);
 306
 307         /* should not be necessary anymore as we use skb_pull_rcsum()
 308          * TODO: please verify this and remove this TODO
 309          * -- Dec 21st 2009, Simon Wunderlich
 310          */
 311
 312         /* skb->ip_summed = CHECKSUM_UNNECESSARY; */
 313
 314         bat_priv->stats.rx_packets++;
 315         bat_priv->stats.rx_bytes += skb->len + ETH_HLEN;
 316
 317         soft_iface->last_rx = jiffies;
 318
 319         if (batadv_is_ap_isolated(bat_priv, ethhdr->h_source, ethhdr->h_dest))
 320                 goto dropped;
 321
 322         /* Let the bridge loop avoidance check the packet. If will
 323          * not handle it, we can safely push it up.
 324          */
 325         if (batadv_bla_rx(bat_priv, skb, vid, is_bcast))
 326                 goto out;
 327
 328         netif_rx(skb);
 329         goto out;
 330
 331 dropped:
 332         kfree_skb(skb);
 333 out:
 334         return;
 335 }
 336
 337 static const struct net_device_ops batadv_netdev_ops = {
 338         .ndo_open = batadv_interface_open,
 339         .ndo_stop = batadv_interface_release,
 340         .ndo_get_stats = batadv_interface_stats,
 341         .ndo_set_mac_address = batadv_interface_set_mac_addr,
 342         .ndo_change_mtu = batadv_interface_change_mtu,
 343         .ndo_start_xmit = batadv_interface_tx,
 344         .ndo_validate_addr = eth_validate_addr
 345 };
 346
 347 static void batadv_interface_setup(struct net_device *dev)
 348 {
 349         struct batadv_priv *priv = netdev_priv(dev);
 350
 351         ether_setup(dev);
 352
 353         dev->netdev_ops = &batadv_netdev_ops;
 354         dev->destructor = free_netdev;
 355         dev->tx_queue_len = 0;
 356
 357         /* can't call min_mtu, because the needed variables
 358          * have not been initialized yet
 359          */
 360         dev->mtu = ETH_DATA_LEN;
 361         /* reserve more space in the skbuff for our header */
 362         dev->hard_header_len = BATADV_HEADER_LEN;
 363
 364         /* generate random address */
 365         eth_hw_addr_random(dev);
 366
 367         SET_ETHTOOL_OPS(dev, &batadv_ethtool_ops);
 368
 369         memset(priv, 0, sizeof(*priv));
 370 }
 371
 372 struct net_device *batadv_softif_create(const char *name)
 373 {
 374         struct net_device *soft_iface;
 375         struct batadv_priv *bat_priv;
 376         int ret;
 377         size_t cnt_len = sizeof(uint64_t) * BATADV_CNT_NUM;
 378
 379         soft_iface = alloc_netdev(sizeof(*bat_priv), name,
 380                                   batadv_interface_setup);
 381
 382         if (!soft_iface)
 383                 goto out;
 384
 385         ret = register_netdevice(soft_iface);
 386         if (ret < 0) {
 387                 pr_err("Unable to register the batman interface '%s': %i\n",
 388                        name, ret);
 389                 goto free_soft_iface;
 390         }
 391
 392         bat_priv = netdev_priv(soft_iface);
 393
 394         atomic_set(&bat_priv->aggregated_ogms, 1);
 395         atomic_set(&bat_priv->bonding, 0);
 396         atomic_set(&bat_priv->bridge_loop_avoidance, 0);
 397         atomic_set(&bat_priv->ap_isolation, 0);
 398         atomic_set(&bat_priv->vis_mode, BATADV_VIS_TYPE_CLIENT_UPDATE);
 399         atomic_set(&bat_priv->gw_mode, BATADV_GW_MODE_OFF);
 400         atomic_set(&bat_priv->gw_sel_class, 20);
 401         atomic_set(&bat_priv->gw_bandwidth, 41);
 402         atomic_set(&bat_priv->orig_interval, 1000);
 403         atomic_set(&bat_priv->hop_penalty, 30);
 404         atomic_set(&bat_priv->log_level, 0);
 405         atomic_set(&bat_priv->fragmentation, 1);
 406         atomic_set(&bat_priv->bcast_queue_left, BATADV_BCAST_QUEUE_LEN);
 407         atomic_set(&bat_priv->batman_queue_left, BATADV_BATMAN_QUEUE_LEN);
 408
 409         atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
 410         atomic_set(&bat_priv->bcast_seqno, 1);
 411         atomic_set(&bat_priv->ttvn, 0);
 412         atomic_set(&bat_priv->tt_local_changes, 0);
 413         atomic_set(&bat_priv->tt_ogm_append_cnt, 0);
 414         atomic_set(&bat_priv->bla_num_requests, 0);
 415
 416         bat_priv->tt_buff = NULL;
 417         bat_priv->tt_buff_len = 0;
 418         bat_priv->tt_poss_change = false;
 419
 420         bat_priv->primary_if = NULL;
 421         bat_priv->num_ifaces = 0;
 422
 423         bat_priv->bat_counters = __alloc_percpu(cnt_len, __alignof__(uint64_t));
 424         if (!bat_priv->bat_counters)
 425                 goto unreg_soft_iface;
 426
 427         ret = batadv_algo_select(bat_priv, batadv_routing_algo);
 428         if (ret < 0)
 429                 goto free_bat_counters;
 430
 431         ret = batadv_sysfs_add_meshif(soft_iface);
 432         if (ret < 0)
 433                 goto free_bat_counters;
 434
 435         ret = batadv_debugfs_add_meshif(soft_iface);
 436         if (ret < 0)
 437                 goto unreg_sysfs;
 438
 439         ret = batadv_mesh_init(soft_iface);
 440         if (ret < 0)
 441                 goto unreg_debugfs;
 442
 443         return soft_iface;
 444
 445 unreg_debugfs:
 446         batadv_debugfs_del_meshif(soft_iface);
 447 unreg_sysfs:
 448         batadv_sysfs_del_meshif(soft_iface);
 449 free_bat_counters:
 450         free_percpu(bat_priv->bat_counters);
 451 unreg_soft_iface:
 452         unregister_netdevice(soft_iface);
 453         return NULL;
 454
 455 free_soft_iface:
 456         free_netdev(soft_iface);
 457 out:
 458         return NULL;
 459 }
 460
 461 void batadv_softif_destroy(struct net_device *soft_iface)
 462 {
 463         batadv_debugfs_del_meshif(soft_iface);
 464         batadv_sysfs_del_meshif(soft_iface);
 465         batadv_mesh_free(soft_iface);
 466         unregister_netdevice(soft_iface);
 467 }
 468
 469 int batadv_softif_is_valid(const struct net_device *net_dev)
 470 {
 471         if (net_dev->netdev_ops->ndo_start_xmit == batadv_interface_tx)
 472                 return 1;
 473
 474         return 0;
 475 }
 476
 477 /* ethtool */
 478 static int batadv_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 479 {
 480         cmd->supported = 0;
 481         cmd->advertising = 0;
 482         ethtool_cmd_speed_set(cmd, SPEED_10);
 483         cmd->duplex = DUPLEX_FULL;
 484         cmd->port = PORT_TP;
 485         cmd->phy_address = 0;
 486         cmd->transceiver = XCVR_INTERNAL;
 487         cmd->autoneg = AUTONEG_DISABLE;
 488         cmd->maxtxpkt = 0;
 489         cmd->maxrxpkt = 0;
 490
 491         return 0;
 492 }
 493
 494 static void batadv_get_drvinfo(struct net_device *dev,
 495                                struct ethtool_drvinfo *info)
 496 {
 497         strcpy(info->driver, "B.A.T.M.A.N. advanced");
 498         strcpy(info->version, BATADV_SOURCE_VERSION);
 499         strcpy(info->fw_version, "N/A");
 500         strcpy(info->bus_info, "batman");
 501 }
 502
 503 static u32 batadv_get_msglevel(struct net_device *dev)
 504 {
 505         return -EOPNOTSUPP;
 506 }
 507
 508 static void batadv_set_msglevel(struct net_device *dev, u32 value)
 509 {
 510 }
 511
 512 static u32 batadv_get_link(struct net_device *dev)
 513 {
 514         return 1;
 515 }
 516
 517 /* Inspired by drivers/net/ethernet/dlink/sundance.c:1702
 518  * Declare each description string in struct.name[] to get fixed sized buffer
 519  * and compile time checking for strings longer than ETH_GSTRING_LEN.
 520  */
 521 static const struct {
 522         const char name[ETH_GSTRING_LEN];
 523 } batadv_counters_strings[] = {
 524         { "forward" },
 525         { "forward_bytes" },
 526         { "mgmt_tx" },
 527         { "mgmt_tx_bytes" },
 528         { "mgmt_rx" },
 529         { "mgmt_rx_bytes" },
 530         { "tt_request_tx" },
 531         { "tt_request_rx" },
 532         { "tt_response_tx" },
 533         { "tt_response_rx" },
 534         { "tt_roam_adv_tx" },
 535         { "tt_roam_adv_rx" },
 536 };
 537
 538 static void batadv_get_strings(struct net_device *dev, uint32_t stringset,
 539                                uint8_t *data)
 540 {
 541         if (stringset == ETH_SS_STATS)
 542                 memcpy(data, batadv_counters_strings,
 543                        sizeof(batadv_counters_strings));
 544 }
 545
 546 static void batadv_get_ethtool_stats(struct net_device *dev,
 547                                      struct ethtool_stats *stats,
 548                                      uint64_t *data)
 549 {
 550         struct batadv_priv *bat_priv = netdev_priv(dev);
 551         int i;
 552
 553         for (i = 0; i < BATADV_CNT_NUM; i++)
 554                 data[i] = batadv_sum_counter(bat_priv, i);
 555 }
 556
 557 static int batadv_get_sset_count(struct net_device *dev, int stringset)
 558 {
 559         if (stringset == ETH_SS_STATS)
 560                 return BATADV_CNT_NUM;
 561
 562         return -EOPNOTSUPP;
 563 }