net/batman-adv/soft-interface.c

   1 /*
   2  * Copyright (C) 2007-2012 B.A.T.M.A.N. contributors:
   3  *
   4  * Marek Lindner, Simon Wunderlich
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of version 2 of the GNU General Public
   8  * License as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  * 02110-1301, USA
  19  *
  20  */
  21
  22 #include "main.h"
  23 #include "soft-interface.h"
  24 #include "hard-interface.h"
  25 #include "routing.h"
  26 #include "send.h"
  27 #include "bat_debugfs.h"
  28 #include "translation-table.h"
  29 #include "hash.h"
  30 #include "gateway_common.h"
  31 #include "gateway_client.h"
  32 #include "bat_sysfs.h"
  33 #include "originator.h"
  34 #include <linux/slab.h>
  35 #include <linux/ethtool.h>
  36 #include <linux/etherdevice.h>
  37 #include <linux/if_vlan.h>
  38 #include "unicast.h"
  39 #include "bridge_loop_avoidance.h"
  40
  41
  42 static int bat_get_settings(struct net_device *dev, struct ethtool_cmd *cmd);
  43 static void bat_get_drvinfo(struct net_device *dev,
  44                             struct ethtool_drvinfo *info);
  45 static u32 bat_get_msglevel(struct net_device *dev);
  46 static void bat_set_msglevel(struct net_device *dev, u32 value);
  47 static u32 bat_get_link(struct net_device *dev);
  48
  49 static const struct ethtool_ops bat_ethtool_ops = {
  50         .get_settings = bat_get_settings,
  51         .get_drvinfo = bat_get_drvinfo,
  52         .get_msglevel = bat_get_msglevel,
  53         .set_msglevel = bat_set_msglevel,
  54         .get_link = bat_get_link,
  55 };
  56
  57 int my_skb_head_push(struct sk_buff *skb, unsigned int len)
  58 {
  59         int result;
  60
  61         /**
  62          * TODO: We must check if we can release all references to non-payload
  63          * data using skb_header_release in our skbs to allow skb_cow_header to
  64          * work optimally. This means that those skbs are not allowed to read
  65          * or write any data which is before the current position of skb->data
  66          * after that call and thus allow other skbs with the same data buffer
  67          * to write freely in that area.
  68          */
  69         result = skb_cow_head(skb, len);
  70         if (result < 0)
  71                 return result;
  72
  73         skb_push(skb, len);
  74         return 0;
  75 }
  76
  77 static int interface_open(struct net_device *dev)
  78 {
  79         netif_start_queue(dev);
  80         return 0;
  81 }
  82
  83 static int interface_release(struct net_device *dev)
  84 {
  85         netif_stop_queue(dev);
  86         return 0;
  87 }
  88
  89 static struct net_device_stats *interface_stats(struct net_device *dev)
  90 {
  91         struct bat_priv *bat_priv = netdev_priv(dev);
  92         return &bat_priv->stats;
  93 }
  94
  95 static int interface_set_mac_addr(struct net_device *dev, void *p)
  96 {
  97         struct bat_priv *bat_priv = netdev_priv(dev);
  98         struct sockaddr *addr = p;
  99
 100         if (!is_valid_ether_addr(addr->sa_data))
 101                 return -EADDRNOTAVAIL;
 102
 103         /* only modify transtable if it has been initialized before */
 104         if (atomic_read(&bat_priv->mesh_state) == MESH_ACTIVE) {
 105                 tt_local_remove(bat_priv, dev->dev_addr,
 106                                 "mac address changed", false);
 107                 tt_local_add(dev, addr->sa_data, NULL_IFINDEX);
 108         }
 109
 110         memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
 111         dev->addr_assign_type &= ~NET_ADDR_RANDOM;
 112         return 0;
 113 }
 114
 115 static int interface_change_mtu(struct net_device *dev, int new_mtu)
 116 {
 117         /* check ranges */
 118         if ((new_mtu < 68) || (new_mtu > hardif_min_mtu(dev)))
 119                 return -EINVAL;
 120
 121         dev->mtu = new_mtu;
 122
 123         return 0;
 124 }
 125
 126 static int interface_tx(struct sk_buff *skb, struct net_device *soft_iface)
 127 {
 128         struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
 129         struct bat_priv *bat_priv = netdev_priv(soft_iface);
 130         struct hard_iface *primary_if = NULL;
 131         struct bcast_packet *bcast_packet;
 132         struct vlan_ethhdr *vhdr;
 133         static const uint8_t stp_addr[ETH_ALEN] = {0x01, 0x80, 0xC2, 0x00, 0x00,
 134                                                    0x00};
 135         unsigned int header_len = 0;
 136         int data_len = skb->len, ret;
 137         short vid __maybe_unused = -1;
 138         bool do_bcast = false;
 139
 140         if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE)
 141                 goto dropped;
 142
 143         soft_iface->trans_start = jiffies;
 144
 145         switch (ntohs(ethhdr->h_proto)) {
 146         case ETH_P_8021Q:
 147                 vhdr = (struct vlan_ethhdr *)skb->data;
 148                 vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;
 149
 150                 if (ntohs(vhdr->h_vlan_encapsulated_proto) != ETH_P_BATMAN)
 151                         break;
 152
 153                 /* fall through */
 154         case ETH_P_BATMAN:
 155                 goto dropped;
 156         }
 157
 158         if (bla_tx(bat_priv, skb, vid))
 159                 goto dropped;
 160
 161         /* Register the client MAC in the transtable */
 162         tt_local_add(soft_iface, ethhdr->h_source, skb->skb_iif);
 163
 164         /* don't accept stp packets. STP does not help in meshes.
 165          * better use the bridge loop avoidance ...
 166          */
 167         if (compare_eth(ethhdr->h_dest, stp_addr))
 168                 goto dropped;
 169
 170         if (is_multicast_ether_addr(ethhdr->h_dest)) {
 171                 do_bcast = true;
 172
 173                 switch (atomic_read(&bat_priv->gw_mode)) {
 174                 case GW_MODE_SERVER:
 175                         /* gateway servers should not send dhcp
 176                          * requests into the mesh */
 177                         ret = gw_is_dhcp_target(skb, &header_len);
 178                         if (ret)
 179                                 goto dropped;
 180                         break;
 181                 case GW_MODE_CLIENT:
 182                         /* gateway clients should send dhcp requests
 183                          * via unicast to their gateway */
 184                         ret = gw_is_dhcp_target(skb, &header_len);
 185                         if (ret)
 186                                 do_bcast = false;
 187                         break;
 188                 case GW_MODE_OFF:
 189                 default:
 190                         break;
 191                 }
 192         }
 193
 194         /* ethernet packet should be broadcasted */
 195         if (do_bcast) {
 196                 primary_if = primary_if_get_selected(bat_priv);
 197                 if (!primary_if)
 198                         goto dropped;
 199
 200                 if (my_skb_head_push(skb, sizeof(*bcast_packet)) < 0)
 201                         goto dropped;
 202
 203                 bcast_packet = (struct bcast_packet *)skb->data;
 204                 bcast_packet->header.version = COMPAT_VERSION;
 205                 bcast_packet->header.ttl = TTL;
 206
 207                 /* batman packet type: broadcast */
 208                 bcast_packet->header.packet_type = BAT_BCAST;
 209
 210                 /* hw address of first interface is the orig mac because only
 211                  * this mac is known throughout the mesh */
 212                 memcpy(bcast_packet->orig,
 213                        primary_if->net_dev->dev_addr, ETH_ALEN);
 214
 215                 /* set broadcast sequence number */
 216                 bcast_packet->seqno =
 217                         htonl(atomic_inc_return(&bat_priv->bcast_seqno));
 218
 219                 add_bcast_packet_to_list(bat_priv, skb, 1);
 220
 221                 /* a copy is stored in the bcast list, therefore removing
 222                  * the original skb. */
 223                 kfree_skb(skb);
 224
 225         /* unicast packet */
 226         } else {
 227                 if (atomic_read(&bat_priv->gw_mode) != GW_MODE_OFF) {
 228                         ret = gw_out_of_range(bat_priv, skb, ethhdr);
 229                         if (ret)
 230                                 goto dropped;
 231                 }
 232
 233                 ret = unicast_send_skb(skb, bat_priv);
 234                 if (ret != 0)
 235                         goto dropped_freed;
 236         }
 237
 238         bat_priv->stats.tx_packets++;
 239         bat_priv->stats.tx_bytes += data_len;
 240         goto end;
 241
 242 dropped:
 243         kfree_skb(skb);
 244 dropped_freed:
 245         bat_priv->stats.tx_dropped++;
 246 end:
 247         if (primary_if)
 248                 hardif_free_ref(primary_if);
 249         return NETDEV_TX_OK;
 250 }
 251
 252 void interface_rx(struct net_device *soft_iface,
 253                   struct sk_buff *skb, struct hard_iface *recv_if,
 254                   int hdr_size)
 255 {
 256         struct bat_priv *bat_priv = netdev_priv(soft_iface);
 257         struct ethhdr *ethhdr;
 258         struct vlan_ethhdr *vhdr;
 259         short vid __maybe_unused = -1;
 260
 261         /* check if enough space is available for pulling, and pull */
 262         if (!pskb_may_pull(skb, hdr_size))
 263                 goto dropped;
 264
 265         skb_pull_rcsum(skb, hdr_size);
 266         skb_reset_mac_header(skb);
 267
 268         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 269
 270         switch (ntohs(ethhdr->h_proto)) {
 271         case ETH_P_8021Q:
 272                 vhdr = (struct vlan_ethhdr *)skb->data;
 273                 vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;
 274
 275                 if (ntohs(vhdr->h_vlan_encapsulated_proto) != ETH_P_BATMAN)
 276                         break;
 277
 278                 /* fall through */
 279         case ETH_P_BATMAN:
 280                 goto dropped;
 281         }
 282
 283         /* skb->dev & skb->pkt_type are set here */
 284         if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
 285                 goto dropped;
 286         skb->protocol = eth_type_trans(skb, soft_iface);
 287
 288         /* should not be necessary anymore as we use skb_pull_rcsum()
 289          * TODO: please verify this and remove this TODO
 290          * -- Dec 21st 2009, Simon Wunderlich */
 291
 292 /*      skb->ip_summed = CHECKSUM_UNNECESSARY;*/
 293
 294         bat_priv->stats.rx_packets++;
 295         bat_priv->stats.rx_bytes += skb->len + ETH_HLEN;
 296
 297         soft_iface->last_rx = jiffies;
 298
 299         if (is_ap_isolated(bat_priv, ethhdr->h_source, ethhdr->h_dest))
 300                 goto dropped;
 301
 302         /* Let the bridge loop avoidance check the packet. If will
 303          * not handle it, we can safely push it up.
 304          */
 305         if (bla_rx(bat_priv, skb, vid))
 306                 goto out;
 307
 308         netif_rx(skb);
 309         goto out;
 310
 311 dropped:
 312         kfree_skb(skb);
 313 out:
 314         return;
 315 }
 316
 317 static const struct net_device_ops bat_netdev_ops = {
 318         .ndo_open = interface_open,
 319         .ndo_stop = interface_release,
 320         .ndo_get_stats = interface_stats,
 321         .ndo_set_mac_address = interface_set_mac_addr,
 322         .ndo_change_mtu = interface_change_mtu,
 323         .ndo_start_xmit = interface_tx,
 324         .ndo_validate_addr = eth_validate_addr
 325 };
 326
 327 static void interface_setup(struct net_device *dev)
 328 {
 329         struct bat_priv *priv = netdev_priv(dev);
 330
 331         ether_setup(dev);
 332
 333         dev->netdev_ops = &bat_netdev_ops;
 334         dev->destructor = free_netdev;
 335         dev->tx_queue_len = 0;
 336
 337         /**
 338          * can't call min_mtu, because the needed variables
 339          * have not been initialized yet
 340          */
 341         dev->mtu = ETH_DATA_LEN;
 342         /* reserve more space in the skbuff for our header */
 343         dev->hard_header_len = BAT_HEADER_LEN;
 344
 345         /* generate random address */
 346         eth_hw_addr_random(dev);
 347
 348         SET_ETHTOOL_OPS(dev, &bat_ethtool_ops);
 349
 350         memset(priv, 0, sizeof(*priv));
 351 }
 352
 353 struct net_device *softif_create(const char *name)
 354 {
 355         struct net_device *soft_iface;
 356         struct bat_priv *bat_priv;
 357         int ret;
 358
 359         soft_iface = alloc_netdev(sizeof(*bat_priv), name, interface_setup);
 360
 361         if (!soft_iface)
 362                 goto out;
 363
 364         ret = register_netdevice(soft_iface);
 365         if (ret < 0) {
 366                 pr_err("Unable to register the batman interface '%s': %i\n",
 367                        name, ret);
 368                 goto free_soft_iface;
 369         }
 370
 371         bat_priv = netdev_priv(soft_iface);
 372
 373         atomic_set(&bat_priv->aggregated_ogms, 1);
 374         atomic_set(&bat_priv->bonding, 0);
 375         atomic_set(&bat_priv->bridge_loop_avoidance, 0);
 376         atomic_set(&bat_priv->ap_isolation, 0);
 377         atomic_set(&bat_priv->vis_mode, VIS_TYPE_CLIENT_UPDATE);
 378         atomic_set(&bat_priv->gw_mode, GW_MODE_OFF);
 379         atomic_set(&bat_priv->gw_sel_class, 20);
 380         atomic_set(&bat_priv->gw_bandwidth, 41);
 381         atomic_set(&bat_priv->orig_interval, 1000);
 382         atomic_set(&bat_priv->hop_penalty, 30);
 383         atomic_set(&bat_priv->log_level, 0);
 384         atomic_set(&bat_priv->fragmentation, 1);
 385         atomic_set(&bat_priv->bcast_queue_left, BCAST_QUEUE_LEN);
 386         atomic_set(&bat_priv->batman_queue_left, BATMAN_QUEUE_LEN);
 387
 388         atomic_set(&bat_priv->mesh_state, MESH_INACTIVE);
 389         atomic_set(&bat_priv->bcast_seqno, 1);
 390         atomic_set(&bat_priv->ttvn, 0);
 391         atomic_set(&bat_priv->tt_local_changes, 0);
 392         atomic_set(&bat_priv->tt_ogm_append_cnt, 0);
 393         atomic_set(&bat_priv->bla_num_requests, 0);
 394
 395         bat_priv->tt_buff = NULL;
 396         bat_priv->tt_buff_len = 0;
 397         bat_priv->tt_poss_change = false;
 398
 399         bat_priv->primary_if = NULL;
 400         bat_priv->num_ifaces = 0;
 401
 402         ret = bat_algo_select(bat_priv, bat_routing_algo);
 403         if (ret < 0)
 404                 goto unreg_soft_iface;
 405
 406         ret = sysfs_add_meshif(soft_iface);
 407         if (ret < 0)
 408                 goto unreg_soft_iface;
 409
 410         ret = debugfs_add_meshif(soft_iface);
 411         if (ret < 0)
 412                 goto unreg_sysfs;
 413
 414         ret = mesh_init(soft_iface);
 415         if (ret < 0)
 416                 goto unreg_debugfs;
 417
 418         return soft_iface;
 419
 420 unreg_debugfs:
 421         debugfs_del_meshif(soft_iface);
 422 unreg_sysfs:
 423         sysfs_del_meshif(soft_iface);
 424 unreg_soft_iface:
 425         unregister_netdevice(soft_iface);
 426         return NULL;
 427
 428 free_soft_iface:
 429         free_netdev(soft_iface);
 430 out:
 431         return NULL;
 432 }
 433
 434 void softif_destroy(struct net_device *soft_iface)
 435 {
 436         debugfs_del_meshif(soft_iface);
 437         sysfs_del_meshif(soft_iface);
 438         mesh_free(soft_iface);
 439         unregister_netdevice(soft_iface);
 440 }
 441
 442 int softif_is_valid(const struct net_device *net_dev)
 443 {
 444         if (net_dev->netdev_ops->ndo_start_xmit == interface_tx)
 445                 return 1;
 446
 447         return 0;
 448 }
 449
 450 /* ethtool */
 451 static int bat_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 452 {
 453         cmd->supported = 0;
 454         cmd->advertising = 0;
 455         ethtool_cmd_speed_set(cmd, SPEED_10);
 456         cmd->duplex = DUPLEX_FULL;
 457         cmd->port = PORT_TP;
 458         cmd->phy_address = 0;
 459         cmd->transceiver = XCVR_INTERNAL;
 460         cmd->autoneg = AUTONEG_DISABLE;
 461         cmd->maxtxpkt = 0;
 462         cmd->maxrxpkt = 0;
 463
 464         return 0;
 465 }
 466
 467 static void bat_get_drvinfo(struct net_device *dev,
 468                             struct ethtool_drvinfo *info)
 469 {
 470         strcpy(info->driver, "B.A.T.M.A.N. advanced");
 471         strcpy(info->version, SOURCE_VERSION);
 472         strcpy(info->fw_version, "N/A");
 473         strcpy(info->bus_info, "batman");
 474 }
 475
 476 static u32 bat_get_msglevel(struct net_device *dev)
 477 {
 478         return -EOPNOTSUPP;
 479 }
 480
 481 static void bat_set_msglevel(struct net_device *dev, u32 value)
 482 {
 483 }
 484
 485 static u32 bat_get_link(struct net_device *dev)
 486 {
 487         return 1;
 488 }