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 "bat_debugfs.h"
  26 #include "translation-table.h"
  27 #include "hash.h"
  28 #include "gateway_common.h"
  29 #include "gateway_client.h"
  30 #include "bat_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 bat_get_settings(struct net_device *dev, struct ethtool_cmd *cmd);
  41 static void bat_get_drvinfo(struct net_device *dev,
  42                             struct ethtool_drvinfo *info);
  43 static u32 bat_get_msglevel(struct net_device *dev);
  44 static void bat_set_msglevel(struct net_device *dev, u32 value);
  45 static u32 bat_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 bat_ethtool_ops = {
  52         .get_settings = bat_get_settings,
  53         .get_drvinfo = bat_get_drvinfo,
  54         .get_msglevel = bat_get_msglevel,
  55         .set_msglevel = bat_set_msglevel,
  56         .get_link = bat_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 interface_open(struct net_device *dev)
  82 {
  83         netif_start_queue(dev);
  84         return 0;
  85 }
  86
  87 static int interface_release(struct net_device *dev)
  88 {
  89         netif_stop_queue(dev);
  90         return 0;
  91 }
  92
  93 static struct net_device_stats *interface_stats(struct net_device *dev)
  94 {
  95         struct bat_priv *bat_priv = netdev_priv(dev);
  96         return &bat_priv->stats;
  97 }
  98
  99 static int interface_set_mac_addr(struct net_device *dev, void *p)
 100 {
 101         struct bat_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) == 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, 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 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 interface_tx(struct sk_buff *skb, struct net_device *soft_iface)
 131 {
 132         struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
 133         struct bat_priv *bat_priv = netdev_priv(soft_iface);
 134         struct hard_iface *primary_if = NULL;
 135         struct bcast_packet *bcast_packet;
 136         struct vlan_ethhdr *vhdr;
 137         static const uint8_t stp_addr[ETH_ALEN] = {0x01, 0x80, 0xC2, 0x00, 0x00,
 138                                                    0x00};
 139         unsigned int header_len = 0;
 140         int data_len = skb->len, ret;
 141         short vid __maybe_unused = -1;
 142         bool do_bcast = false;
 143
 144         if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE)
 145                 goto dropped;
 146
 147         soft_iface->trans_start = jiffies;
 148
 149         switch (ntohs(ethhdr->h_proto)) {
 150         case ETH_P_8021Q:
 151                 vhdr = (struct vlan_ethhdr *)skb->data;
 152                 vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;
 153
 154                 if (ntohs(vhdr->h_vlan_encapsulated_proto) != ETH_P_BATMAN)
 155                         break;
 156
 157                 /* fall through */
 158         case ETH_P_BATMAN:
 159                 goto dropped;
 160         }
 161
 162         if (batadv_bla_tx(bat_priv, skb, vid))
 163                 goto dropped;
 164
 165         /* Register the client MAC in the transtable */
 166         batadv_tt_local_add(soft_iface, ethhdr->h_source, skb->skb_iif);
 167
 168         /* don't accept stp packets. STP does not help in meshes.
 169          * better use the bridge loop avoidance ...
 170          */
 171         if (compare_eth(ethhdr->h_dest, stp_addr))
 172                 goto dropped;
 173
 174         if (is_multicast_ether_addr(ethhdr->h_dest)) {
 175                 do_bcast = true;
 176
 177                 switch (atomic_read(&bat_priv->gw_mode)) {
 178                 case GW_MODE_SERVER:
 179                         /* gateway servers should not send dhcp
 180                          * requests into the mesh
 181                          */
 182                         ret = batadv_gw_is_dhcp_target(skb, &header_len);
 183                         if (ret)
 184                                 goto dropped;
 185                         break;
 186                 case GW_MODE_CLIENT:
 187                         /* gateway clients should send dhcp requests
 188                          * via unicast to their gateway
 189                          */
 190                         ret = batadv_gw_is_dhcp_target(skb, &header_len);
 191                         if (ret)
 192                                 do_bcast = false;
 193                         break;
 194                 case GW_MODE_OFF:
 195                 default:
 196                         break;
 197                 }
 198         }
 199
 200         /* ethernet packet should be broadcasted */
 201         if (do_bcast) {
 202                 primary_if = primary_if_get_selected(bat_priv);
 203                 if (!primary_if)
 204                         goto dropped;
 205
 206                 if (batadv_skb_head_push(skb, sizeof(*bcast_packet)) < 0)
 207                         goto dropped;
 208
 209                 bcast_packet = (struct bcast_packet *)skb->data;
 210                 bcast_packet->header.version = COMPAT_VERSION;
 211                 bcast_packet->header.ttl = TTL;
 212
 213                 /* batman packet type: broadcast */
 214                 bcast_packet->header.packet_type = BAT_BCAST;
 215
 216                 /* hw address of first interface is the orig mac because only
 217                  * this mac is known throughout the mesh
 218                  */
 219                 memcpy(bcast_packet->orig,
 220                        primary_if->net_dev->dev_addr, ETH_ALEN);
 221
 222                 /* set broadcast sequence number */
 223                 bcast_packet->seqno =
 224                         htonl(atomic_inc_return(&bat_priv->bcast_seqno));
 225
 226                 batadv_add_bcast_packet_to_list(bat_priv, skb, 1);
 227
 228                 /* a copy is stored in the bcast list, therefore removing
 229                  * the original skb.
 230                  */
 231                 kfree_skb(skb);
 232
 233         /* unicast packet */
 234         } else {
 235                 if (atomic_read(&bat_priv->gw_mode) != GW_MODE_OFF) {
 236                         ret = batadv_gw_out_of_range(bat_priv, skb, ethhdr);
 237                         if (ret)
 238                                 goto dropped;
 239                 }
 240
 241                 ret = batadv_unicast_send_skb(skb, bat_priv);
 242                 if (ret != 0)
 243                         goto dropped_freed;
 244         }
 245
 246         bat_priv->stats.tx_packets++;
 247         bat_priv->stats.tx_bytes += data_len;
 248         goto end;
 249
 250 dropped:
 251         kfree_skb(skb);
 252 dropped_freed:
 253         bat_priv->stats.tx_dropped++;
 254 end:
 255         if (primary_if)
 256                 hardif_free_ref(primary_if);
 257         return NETDEV_TX_OK;
 258 }
 259
 260 void batadv_interface_rx(struct net_device *soft_iface,
 261                          struct sk_buff *skb, struct hard_iface *recv_if,
 262                          int hdr_size)
 263 {
 264         struct bat_priv *bat_priv = netdev_priv(soft_iface);
 265         struct ethhdr *ethhdr;
 266         struct vlan_ethhdr *vhdr;
 267         short vid __maybe_unused = -1;
 268
 269         /* check if enough space is available for pulling, and pull */
 270         if (!pskb_may_pull(skb, hdr_size))
 271                 goto dropped;
 272
 273         skb_pull_rcsum(skb, hdr_size);
 274         skb_reset_mac_header(skb);
 275
 276         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 277
 278         switch (ntohs(ethhdr->h_proto)) {
 279         case ETH_P_8021Q:
 280                 vhdr = (struct vlan_ethhdr *)skb->data;
 281                 vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;
 282
 283                 if (ntohs(vhdr->h_vlan_encapsulated_proto) != ETH_P_BATMAN)
 284                         break;
 285
 286                 /* fall through */
 287         case ETH_P_BATMAN:
 288                 goto dropped;
 289         }
 290
 291         /* skb->dev & skb->pkt_type are set here */
 292         if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
 293                 goto dropped;
 294         skb->protocol = eth_type_trans(skb, soft_iface);
 295
 296         /* should not be necessary anymore as we use skb_pull_rcsum()
 297          * TODO: please verify this and remove this TODO
 298          * -- Dec 21st 2009, Simon Wunderlich
 299          */
 300
 301         /* skb->ip_summed = CHECKSUM_UNNECESSARY; */
 302
 303         bat_priv->stats.rx_packets++;
 304         bat_priv->stats.rx_bytes += skb->len + ETH_HLEN;
 305
 306         soft_iface->last_rx = jiffies;
 307
 308         if (batadv_is_ap_isolated(bat_priv, ethhdr->h_source, ethhdr->h_dest))
 309                 goto dropped;
 310
 311         /* Let the bridge loop avoidance check the packet. If will
 312          * not handle it, we can safely push it up.
 313          */
 314         if (batadv_bla_rx(bat_priv, skb, vid))
 315                 goto out;
 316
 317         netif_rx(skb);
 318         goto out;
 319
 320 dropped:
 321         kfree_skb(skb);
 322 out:
 323         return;
 324 }
 325
 326 static const struct net_device_ops bat_netdev_ops = {
 327         .ndo_open = interface_open,
 328         .ndo_stop = interface_release,
 329         .ndo_get_stats = interface_stats,
 330         .ndo_set_mac_address = interface_set_mac_addr,
 331         .ndo_change_mtu = interface_change_mtu,
 332         .ndo_start_xmit = interface_tx,
 333         .ndo_validate_addr = eth_validate_addr
 334 };
 335
 336 static void interface_setup(struct net_device *dev)
 337 {
 338         struct bat_priv *priv = netdev_priv(dev);
 339
 340         ether_setup(dev);
 341
 342         dev->netdev_ops = &bat_netdev_ops;
 343         dev->destructor = free_netdev;
 344         dev->tx_queue_len = 0;
 345
 346         /* can't call min_mtu, because the needed variables
 347          * have not been initialized yet
 348          */
 349         dev->mtu = ETH_DATA_LEN;
 350         /* reserve more space in the skbuff for our header */
 351         dev->hard_header_len = BAT_HEADER_LEN;
 352
 353         /* generate random address */
 354         eth_hw_addr_random(dev);
 355
 356         SET_ETHTOOL_OPS(dev, &bat_ethtool_ops);
 357
 358         memset(priv, 0, sizeof(*priv));
 359 }
 360
 361 struct net_device *batadv_softif_create(const char *name)
 362 {
 363         struct net_device *soft_iface;
 364         struct bat_priv *bat_priv;
 365         int ret;
 366
 367         soft_iface = alloc_netdev(sizeof(*bat_priv), name, interface_setup);
 368
 369         if (!soft_iface)
 370                 goto out;
 371
 372         ret = register_netdevice(soft_iface);
 373         if (ret < 0) {
 374                 pr_err("Unable to register the batman interface '%s': %i\n",
 375                        name, ret);
 376                 goto free_soft_iface;
 377         }
 378
 379         bat_priv = netdev_priv(soft_iface);
 380
 381         atomic_set(&bat_priv->aggregated_ogms, 1);
 382         atomic_set(&bat_priv->bonding, 0);
 383         atomic_set(&bat_priv->bridge_loop_avoidance, 0);
 384         atomic_set(&bat_priv->ap_isolation, 0);
 385         atomic_set(&bat_priv->vis_mode, VIS_TYPE_CLIENT_UPDATE);
 386         atomic_set(&bat_priv->gw_mode, GW_MODE_OFF);
 387         atomic_set(&bat_priv->gw_sel_class, 20);
 388         atomic_set(&bat_priv->gw_bandwidth, 41);
 389         atomic_set(&bat_priv->orig_interval, 1000);
 390         atomic_set(&bat_priv->hop_penalty, 30);
 391         atomic_set(&bat_priv->log_level, 0);
 392         atomic_set(&bat_priv->fragmentation, 1);
 393         atomic_set(&bat_priv->bcast_queue_left, BCAST_QUEUE_LEN);
 394         atomic_set(&bat_priv->batman_queue_left, BATMAN_QUEUE_LEN);
 395
 396         atomic_set(&bat_priv->mesh_state, MESH_INACTIVE);
 397         atomic_set(&bat_priv->bcast_seqno, 1);
 398         atomic_set(&bat_priv->ttvn, 0);
 399         atomic_set(&bat_priv->tt_local_changes, 0);
 400         atomic_set(&bat_priv->tt_ogm_append_cnt, 0);
 401         atomic_set(&bat_priv->bla_num_requests, 0);
 402
 403         bat_priv->tt_buff = NULL;
 404         bat_priv->tt_buff_len = 0;
 405         bat_priv->tt_poss_change = false;
 406
 407         bat_priv->primary_if = NULL;
 408         bat_priv->num_ifaces = 0;
 409
 410         bat_priv->bat_counters = __alloc_percpu(sizeof(uint64_t) * BAT_CNT_NUM,
 411                                                 __alignof__(uint64_t));
 412         if (!bat_priv->bat_counters)
 413                 goto unreg_soft_iface;
 414
 415         ret = batadv_algo_select(bat_priv, batadv_routing_algo);
 416         if (ret < 0)
 417                 goto free_bat_counters;
 418
 419         ret = batadv_sysfs_add_meshif(soft_iface);
 420         if (ret < 0)
 421                 goto free_bat_counters;
 422
 423         ret = batadv_debugfs_add_meshif(soft_iface);
 424         if (ret < 0)
 425                 goto unreg_sysfs;
 426
 427         ret = batadv_mesh_init(soft_iface);
 428         if (ret < 0)
 429                 goto unreg_debugfs;
 430
 431         return soft_iface;
 432
 433 unreg_debugfs:
 434         batadv_debugfs_del_meshif(soft_iface);
 435 unreg_sysfs:
 436         batadv_sysfs_del_meshif(soft_iface);
 437 free_bat_counters:
 438         free_percpu(bat_priv->bat_counters);
 439 unreg_soft_iface:
 440         unregister_netdevice(soft_iface);
 441         return NULL;
 442
 443 free_soft_iface:
 444         free_netdev(soft_iface);
 445 out:
 446         return NULL;
 447 }
 448
 449 void batadv_softif_destroy(struct net_device *soft_iface)
 450 {
 451         batadv_debugfs_del_meshif(soft_iface);
 452         batadv_sysfs_del_meshif(soft_iface);
 453         batadv_mesh_free(soft_iface);
 454         unregister_netdevice(soft_iface);
 455 }
 456
 457 int batadv_softif_is_valid(const struct net_device *net_dev)
 458 {
 459         if (net_dev->netdev_ops->ndo_start_xmit == interface_tx)
 460                 return 1;
 461
 462         return 0;
 463 }
 464
 465 /* ethtool */
 466 static int bat_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 467 {
 468         cmd->supported = 0;
 469         cmd->advertising = 0;
 470         ethtool_cmd_speed_set(cmd, SPEED_10);
 471         cmd->duplex = DUPLEX_FULL;
 472         cmd->port = PORT_TP;
 473         cmd->phy_address = 0;
 474         cmd->transceiver = XCVR_INTERNAL;
 475         cmd->autoneg = AUTONEG_DISABLE;
 476         cmd->maxtxpkt = 0;
 477         cmd->maxrxpkt = 0;
 478
 479         return 0;
 480 }
 481
 482 static void bat_get_drvinfo(struct net_device *dev,
 483                             struct ethtool_drvinfo *info)
 484 {
 485         strcpy(info->driver, "B.A.T.M.A.N. advanced");
 486         strcpy(info->version, SOURCE_VERSION);
 487         strcpy(info->fw_version, "N/A");
 488         strcpy(info->bus_info, "batman");
 489 }
 490
 491 static u32 bat_get_msglevel(struct net_device *dev)
 492 {
 493         return -EOPNOTSUPP;
 494 }
 495
 496 static void bat_set_msglevel(struct net_device *dev, u32 value)
 497 {
 498 }
 499
 500 static u32 bat_get_link(struct net_device *dev)
 501 {
 502         return 1;
 503 }
 504
 505 /* Inspired by drivers/net/ethernet/dlink/sundance.c:1702
 506  * Declare each description string in struct.name[] to get fixed sized buffer
 507  * and compile time checking for strings longer than ETH_GSTRING_LEN.
 508  */
 509 static const struct {
 510         const char name[ETH_GSTRING_LEN];
 511 } bat_counters_strings[] = {
 512         { "forward" },
 513         { "forward_bytes" },
 514         { "mgmt_tx" },
 515         { "mgmt_tx_bytes" },
 516         { "mgmt_rx" },
 517         { "mgmt_rx_bytes" },
 518         { "tt_request_tx" },
 519         { "tt_request_rx" },
 520         { "tt_response_tx" },
 521         { "tt_response_rx" },
 522         { "tt_roam_adv_tx" },
 523         { "tt_roam_adv_rx" },
 524 };
 525
 526 static void batadv_get_strings(struct net_device *dev, uint32_t stringset,
 527                                uint8_t *data)
 528 {
 529         if (stringset == ETH_SS_STATS)
 530                 memcpy(data, bat_counters_strings,
 531                        sizeof(bat_counters_strings));
 532 }
 533
 534 static void batadv_get_ethtool_stats(struct net_device *dev,
 535                                      struct ethtool_stats *stats,
 536                                      uint64_t *data)
 537 {
 538         struct bat_priv *bat_priv = netdev_priv(dev);
 539         int i;
 540
 541         for (i = 0; i < BAT_CNT_NUM; i++)
 542                 data[i] = batadv_sum_counter(bat_priv, i);
 543 }
 544
 545 static int batadv_get_sset_count(struct net_device *dev, int stringset)
 546 {
 547         if (stringset == ETH_SS_STATS)
 548                 return BAT_CNT_NUM;
 549
 550         return -EOPNOTSUPP;
 551 }