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