net/batman-adv/soft-interface.c

   1 /* Copyright (C) 2007-2016  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, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "soft-interface.h"
  19 #include "main.h"
  20
  21 #include <linux/atomic.h>
  22 #include <linux/byteorder/generic.h>
  23 #include <linux/cache.h>
  24 #include <linux/compiler.h>
  25 #include <linux/errno.h>
  26 #include <linux/etherdevice.h>
  27 #include <linux/ethtool.h>
  28 #include <linux/fs.h>
  29 #include <linux/if_ether.h>
  30 #include <linux/if_vlan.h>
  31 #include <linux/jiffies.h>
  32 #include <linux/kernel.h>
  33 #include <linux/kref.h>
  34 #include <linux/list.h>
  35 #include <linux/lockdep.h>
  36 #include <linux/netdevice.h>
  37 #include <linux/percpu.h>
  38 #include <linux/printk.h>
  39 #include <linux/random.h>
  40 #include <linux/rculist.h>
  41 #include <linux/rcupdate.h>
  42 #include <linux/skbuff.h>
  43 #include <linux/slab.h>
  44 #include <linux/socket.h>
  45 #include <linux/spinlock.h>
  46 #include <linux/stddef.h>
  47 #include <linux/string.h>
  48 #include <linux/types.h>
  49 #include <linux/workqueue.h>
  50
  51 #include "bridge_loop_avoidance.h"
  52 #include "debugfs.h"
  53 #include "distributed-arp-table.h"
  54 #include "gateway_client.h"
  55 #include "gateway_common.h"
  56 #include "hard-interface.h"
  57 #include "multicast.h"
  58 #include "network-coding.h"
  59 #include "packet.h"
  60 #include "send.h"
  61 #include "sysfs.h"
  62 #include "translation-table.h"
  63
  64 static int batadv_get_settings(struct net_device *dev, struct ethtool_cmd *cmd);
  65 static void batadv_get_drvinfo(struct net_device *dev,
  66                                struct ethtool_drvinfo *info);
  67 static u32 batadv_get_msglevel(struct net_device *dev);
  68 static void batadv_set_msglevel(struct net_device *dev, u32 value);
  69 static u32 batadv_get_link(struct net_device *dev);
  70 static void batadv_get_strings(struct net_device *dev, u32 stringset, u8 *data);
  71 static void batadv_get_ethtool_stats(struct net_device *dev,
  72                                      struct ethtool_stats *stats, u64 *data);
  73 static int batadv_get_sset_count(struct net_device *dev, int stringset);
  74
  75 static const struct ethtool_ops batadv_ethtool_ops = {
  76         .get_settings = batadv_get_settings,
  77         .get_drvinfo = batadv_get_drvinfo,
  78         .get_msglevel = batadv_get_msglevel,
  79         .set_msglevel = batadv_set_msglevel,
  80         .get_link = batadv_get_link,
  81         .get_strings = batadv_get_strings,
  82         .get_ethtool_stats = batadv_get_ethtool_stats,
  83         .get_sset_count = batadv_get_sset_count,
  84 };
  85
  86 int batadv_skb_head_push(struct sk_buff *skb, unsigned int len)
  87 {
  88         int result;
  89
  90         /* TODO: We must check if we can release all references to non-payload
  91          * data using skb_header_release in our skbs to allow skb_cow_header to
  92          * work optimally. This means that those skbs are not allowed to read
  93          * or write any data which is before the current position of skb->data
  94          * after that call and thus allow other skbs with the same data buffer
  95          * to write freely in that area.
  96          */
  97         result = skb_cow_head(skb, len);
  98         if (result < 0)
  99                 return result;
 100
 101         skb_push(skb, len);
 102         return 0;
 103 }
 104
 105 static int batadv_interface_open(struct net_device *dev)
 106 {
 107         netif_start_queue(dev);
 108         return 0;
 109 }
 110
 111 static int batadv_interface_release(struct net_device *dev)
 112 {
 113         netif_stop_queue(dev);
 114         return 0;
 115 }
 116
 117 static struct net_device_stats *batadv_interface_stats(struct net_device *dev)
 118 {
 119         struct batadv_priv *bat_priv = netdev_priv(dev);
 120         struct net_device_stats *stats = &bat_priv->stats;
 121
 122         stats->tx_packets = batadv_sum_counter(bat_priv, BATADV_CNT_TX);
 123         stats->tx_bytes = batadv_sum_counter(bat_priv, BATADV_CNT_TX_BYTES);
 124         stats->tx_dropped = batadv_sum_counter(bat_priv, BATADV_CNT_TX_DROPPED);
 125         stats->rx_packets = batadv_sum_counter(bat_priv, BATADV_CNT_RX);
 126         stats->rx_bytes = batadv_sum_counter(bat_priv, BATADV_CNT_RX_BYTES);
 127         return stats;
 128 }
 129
 130 static int batadv_interface_set_mac_addr(struct net_device *dev, void *p)
 131 {
 132         struct batadv_priv *bat_priv = netdev_priv(dev);
 133         struct batadv_softif_vlan *vlan;
 134         struct sockaddr *addr = p;
 135         u8 old_addr[ETH_ALEN];
 136
 137         if (!is_valid_ether_addr(addr->sa_data))
 138                 return -EADDRNOTAVAIL;
 139
 140         ether_addr_copy(old_addr, dev->dev_addr);
 141         ether_addr_copy(dev->dev_addr, addr->sa_data);
 142
 143         /* only modify transtable if it has been initialized before */
 144         if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
 145                 return 0;
 146
 147         rcu_read_lock();
 148         hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
 149                 batadv_tt_local_remove(bat_priv, old_addr, vlan->vid,
 150                                        "mac address changed", false);
 151                 batadv_tt_local_add(dev, addr->sa_data, vlan->vid,
 152                                     BATADV_NULL_IFINDEX, BATADV_NO_MARK);
 153         }
 154         rcu_read_unlock();
 155
 156         return 0;
 157 }
 158
 159 static int batadv_interface_change_mtu(struct net_device *dev, int new_mtu)
 160 {
 161         /* check ranges */
 162         if ((new_mtu < 68) || (new_mtu > batadv_hardif_min_mtu(dev)))
 163                 return -EINVAL;
 164
 165         dev->mtu = new_mtu;
 166
 167         return 0;
 168 }
 169
 170 /**
 171  * batadv_interface_set_rx_mode - set the rx mode of a device
 172  * @dev: registered network device to modify
 173  *
 174  * We do not actually need to set any rx filters for the virtual batman
 175  * soft interface. However a dummy handler enables a user to set static
 176  * multicast listeners for instance.
 177  */
 178 static void batadv_interface_set_rx_mode(struct net_device *dev)
 179 {
 180 }
 181
 182 static int batadv_interface_tx(struct sk_buff *skb,
 183                                struct net_device *soft_iface)
 184 {
 185         struct ethhdr *ethhdr;
 186         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 187         struct batadv_hard_iface *primary_if = NULL;
 188         struct batadv_bcast_packet *bcast_packet;
 189         __be16 ethertype = htons(ETH_P_BATMAN);
 190         static const u8 stp_addr[ETH_ALEN] = {0x01, 0x80, 0xC2, 0x00,
 191                                               0x00, 0x00};
 192         static const u8 ectp_addr[ETH_ALEN] = {0xCF, 0x00, 0x00, 0x00,
 193                                                0x00, 0x00};
 194         enum batadv_dhcp_recipient dhcp_rcp = BATADV_DHCP_NO;
 195         u8 *dst_hint = NULL, chaddr[ETH_ALEN];
 196         struct vlan_ethhdr *vhdr;
 197         unsigned int header_len = 0;
 198         int data_len = skb->len, ret;
 199         unsigned long brd_delay = 1;
 200         bool do_bcast = false, client_added;
 201         unsigned short vid;
 202         u32 seqno;
 203         int gw_mode;
 204         enum batadv_forw_mode forw_mode;
 205         struct batadv_orig_node *mcast_single_orig = NULL;
 206         int network_offset = ETH_HLEN;
 207
 208         if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
 209                 goto dropped;
 210
 211         soft_iface->trans_start = jiffies;
 212         vid = batadv_get_vid(skb, 0);
 213         ethhdr = eth_hdr(skb);
 214
 215         switch (ntohs(ethhdr->h_proto)) {
 216         case ETH_P_8021Q:
 217                 vhdr = vlan_eth_hdr(skb);
 218
 219                 if (vhdr->h_vlan_encapsulated_proto != ethertype) {
 220                         network_offset += VLAN_HLEN;
 221                         break;
 222                 }
 223
 224                 /* fall through */
 225         case ETH_P_BATMAN:
 226                 goto dropped;
 227         }
 228
 229         skb_set_network_header(skb, network_offset);
 230
 231         if (batadv_bla_tx(bat_priv, skb, vid))
 232                 goto dropped;
 233
 234         /* skb->data might have been reallocated by batadv_bla_tx() */
 235         ethhdr = eth_hdr(skb);
 236
 237         /* Register the client MAC in the transtable */
 238         if (!is_multicast_ether_addr(ethhdr->h_source)) {
 239                 client_added = batadv_tt_local_add(soft_iface, ethhdr->h_source,
 240                                                    vid, skb->skb_iif,
 241                                                    skb->mark);
 242                 if (!client_added)
 243                         goto dropped;
 244         }
 245
 246         /* don't accept stp packets. STP does not help in meshes.
 247          * better use the bridge loop avoidance ...
 248          *
 249          * The same goes for ECTP sent at least by some Cisco Switches,
 250          * it might confuse the mesh when used with bridge loop avoidance.
 251          */
 252         if (batadv_compare_eth(ethhdr->h_dest, stp_addr))
 253                 goto dropped;
 254
 255         if (batadv_compare_eth(ethhdr->h_dest, ectp_addr))
 256                 goto dropped;
 257
 258         gw_mode = atomic_read(&bat_priv->gw_mode);
 259         if (is_multicast_ether_addr(ethhdr->h_dest)) {
 260                 /* if gw mode is off, broadcast every packet */
 261                 if (gw_mode == BATADV_GW_MODE_OFF) {
 262                         do_bcast = true;
 263                         goto send;
 264                 }
 265
 266                 dhcp_rcp = batadv_gw_dhcp_recipient_get(skb, &header_len,
 267                                                         chaddr);
 268                 /* skb->data may have been modified by
 269                  * batadv_gw_dhcp_recipient_get()
 270                  */
 271                 ethhdr = eth_hdr(skb);
 272                 /* if gw_mode is on, broadcast any non-DHCP message.
 273                  * All the DHCP packets are going to be sent as unicast
 274                  */
 275                 if (dhcp_rcp == BATADV_DHCP_NO) {
 276                         do_bcast = true;
 277                         goto send;
 278                 }
 279
 280                 if (dhcp_rcp == BATADV_DHCP_TO_CLIENT)
 281                         dst_hint = chaddr;
 282                 else if ((gw_mode == BATADV_GW_MODE_SERVER) &&
 283                          (dhcp_rcp == BATADV_DHCP_TO_SERVER))
 284                         /* gateways should not forward any DHCP message if
 285                          * directed to a DHCP server
 286                          */
 287                         goto dropped;
 288
 289 send:
 290                 if (do_bcast && !is_broadcast_ether_addr(ethhdr->h_dest)) {
 291                         forw_mode = batadv_mcast_forw_mode(bat_priv, skb,
 292                                                            &mcast_single_orig);
 293                         if (forw_mode == BATADV_FORW_NONE)
 294                                 goto dropped;
 295
 296                         if (forw_mode == BATADV_FORW_SINGLE)
 297                                 do_bcast = false;
 298                 }
 299         }
 300
 301         batadv_skb_set_priority(skb, 0);
 302
 303         /* ethernet packet should be broadcasted */
 304         if (do_bcast) {
 305                 primary_if = batadv_primary_if_get_selected(bat_priv);
 306                 if (!primary_if)
 307                         goto dropped;
 308
 309                 /* in case of ARP request, we do not immediately broadcasti the
 310                  * packet, instead we first wait for DAT to try to retrieve the
 311                  * correct ARP entry
 312                  */
 313                 if (batadv_dat_snoop_outgoing_arp_request(bat_priv, skb))
 314                         brd_delay = msecs_to_jiffies(ARP_REQ_DELAY);
 315
 316                 if (batadv_skb_head_push(skb, sizeof(*bcast_packet)) < 0)
 317                         goto dropped;
 318
 319                 bcast_packet = (struct batadv_bcast_packet *)skb->data;
 320                 bcast_packet->version = BATADV_COMPAT_VERSION;
 321                 bcast_packet->ttl = BATADV_TTL;
 322
 323                 /* batman packet type: broadcast */
 324                 bcast_packet->packet_type = BATADV_BCAST;
 325                 bcast_packet->reserved = 0;
 326
 327                 /* hw address of first interface is the orig mac because only
 328                  * this mac is known throughout the mesh
 329                  */
 330                 ether_addr_copy(bcast_packet->orig,
 331                                 primary_if->net_dev->dev_addr);
 332
 333                 /* set broadcast sequence number */
 334                 seqno = atomic_inc_return(&bat_priv->bcast_seqno);
 335                 bcast_packet->seqno = htonl(seqno);
 336
 337                 batadv_add_bcast_packet_to_list(bat_priv, skb, brd_delay);
 338
 339                 /* a copy is stored in the bcast list, therefore removing
 340                  * the original skb.
 341                  */
 342                 kfree_skb(skb);
 343
 344         /* unicast packet */
 345         } else {
 346                 /* DHCP packets going to a server will use the GW feature */
 347                 if (dhcp_rcp == BATADV_DHCP_TO_SERVER) {
 348                         ret = batadv_gw_out_of_range(bat_priv, skb);
 349                         if (ret)
 350                                 goto dropped;
 351                         ret = batadv_send_skb_via_gw(bat_priv, skb, vid);
 352                 } else if (mcast_single_orig) {
 353                         ret = batadv_send_skb_unicast(bat_priv, skb,
 354                                                       BATADV_UNICAST, 0,
 355                                                       mcast_single_orig, vid);
 356                 } else {
 357                         if (batadv_dat_snoop_outgoing_arp_request(bat_priv,
 358                                                                   skb))
 359                                 goto dropped;
 360
 361                         batadv_dat_snoop_outgoing_arp_reply(bat_priv, skb);
 362
 363                         ret = batadv_send_skb_via_tt(bat_priv, skb, dst_hint,
 364                                                      vid);
 365                 }
 366                 if (ret == NET_XMIT_DROP)
 367                         goto dropped_freed;
 368         }
 369
 370         batadv_inc_counter(bat_priv, BATADV_CNT_TX);
 371         batadv_add_counter(bat_priv, BATADV_CNT_TX_BYTES, data_len);
 372         goto end;
 373
 374 dropped:
 375         kfree_skb(skb);
 376 dropped_freed:
 377         batadv_inc_counter(bat_priv, BATADV_CNT_TX_DROPPED);
 378 end:
 379         if (primary_if)
 380                 batadv_hardif_put(primary_if);
 381         return NETDEV_TX_OK;
 382 }
 383
 384 void batadv_interface_rx(struct net_device *soft_iface,
 385                          struct sk_buff *skb, struct batadv_hard_iface *recv_if,
 386                          int hdr_size, struct batadv_orig_node *orig_node)
 387 {
 388         struct batadv_bcast_packet *batadv_bcast_packet;
 389         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 390         __be16 ethertype = htons(ETH_P_BATMAN);
 391         struct vlan_ethhdr *vhdr;
 392         struct ethhdr *ethhdr;
 393         unsigned short vid;
 394         bool is_bcast;
 395
 396         batadv_bcast_packet = (struct batadv_bcast_packet *)skb->data;
 397         is_bcast = (batadv_bcast_packet->packet_type == BATADV_BCAST);
 398
 399         /* check if enough space is available for pulling, and pull */
 400         if (!pskb_may_pull(skb, hdr_size))
 401                 goto dropped;
 402
 403         skb_pull_rcsum(skb, hdr_size);
 404         skb_reset_mac_header(skb);
 405
 406         /* clean the netfilter state now that the batman-adv header has been
 407          * removed
 408          */
 409         nf_reset(skb);
 410
 411         if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
 412                 goto dropped;
 413
 414         vid = batadv_get_vid(skb, 0);
 415         ethhdr = eth_hdr(skb);
 416
 417         switch (ntohs(ethhdr->h_proto)) {
 418         case ETH_P_8021Q:
 419                 if (!pskb_may_pull(skb, VLAN_ETH_HLEN))
 420                         goto dropped;
 421
 422                 vhdr = (struct vlan_ethhdr *)skb->data;
 423
 424                 if (vhdr->h_vlan_encapsulated_proto != ethertype)
 425                         break;
 426
 427                 /* fall through */
 428         case ETH_P_BATMAN:
 429                 goto dropped;
 430         }
 431
 432         /* skb->dev & skb->pkt_type are set here */
 433         skb->protocol = eth_type_trans(skb, soft_iface);
 434
 435         /* should not be necessary anymore as we use skb_pull_rcsum()
 436          * TODO: please verify this and remove this TODO
 437          * -- Dec 21st 2009, Simon Wunderlich
 438          */
 439
 440         /* skb->ip_summed = CHECKSUM_UNNECESSARY; */
 441
 442         batadv_inc_counter(bat_priv, BATADV_CNT_RX);
 443         batadv_add_counter(bat_priv, BATADV_CNT_RX_BYTES,
 444                            skb->len + ETH_HLEN);
 445
 446         soft_iface->last_rx = jiffies;
 447
 448         /* Let the bridge loop avoidance check the packet. If will
 449          * not handle it, we can safely push it up.
 450          */
 451         if (batadv_bla_rx(bat_priv, skb, vid, is_bcast))
 452                 goto out;
 453
 454         if (orig_node)
 455                 batadv_tt_add_temporary_global_entry(bat_priv, orig_node,
 456                                                      ethhdr->h_source, vid);
 457
 458         if (is_multicast_ether_addr(ethhdr->h_dest)) {
 459                 /* set the mark on broadcast packets if AP isolation is ON and
 460                  * the packet is coming from an "isolated" client
 461                  */
 462                 if (batadv_vlan_ap_isola_get(bat_priv, vid) &&
 463                     batadv_tt_global_is_isolated(bat_priv, ethhdr->h_source,
 464                                                  vid)) {
 465                         /* save bits in skb->mark not covered by the mask and
 466                          * apply the mark on the rest
 467                          */
 468                         skb->mark &= ~bat_priv->isolation_mark_mask;
 469                         skb->mark |= bat_priv->isolation_mark;
 470                 }
 471         } else if (batadv_is_ap_isolated(bat_priv, ethhdr->h_source,
 472                                          ethhdr->h_dest, vid)) {
 473                 goto dropped;
 474         }
 475
 476         netif_rx(skb);
 477         goto out;
 478
 479 dropped:
 480         kfree_skb(skb);
 481 out:
 482         return;
 483 }
 484
 485 /**
 486  * batadv_softif_vlan_release - release vlan from lists and queue for free after
 487  *  rcu grace period
 488  * @ref: kref pointer of the vlan object
 489  */
 490 static void batadv_softif_vlan_release(struct kref *ref)
 491 {
 492         struct batadv_softif_vlan *vlan;
 493
 494         vlan = container_of(ref, struct batadv_softif_vlan, refcount);
 495
 496         spin_lock_bh(&vlan->bat_priv->softif_vlan_list_lock);
 497         hlist_del_rcu(&vlan->list);
 498         spin_unlock_bh(&vlan->bat_priv->softif_vlan_list_lock);
 499
 500         kfree_rcu(vlan, rcu);
 501 }
 502
 503 /**
 504  * batadv_softif_vlan_put - decrease the vlan object refcounter and
 505  *  possibly release it
 506  * @vlan: the vlan object to release
 507  */
 508 void batadv_softif_vlan_put(struct batadv_softif_vlan *vlan)
 509 {
 510         if (!vlan)
 511                 return;
 512
 513         kref_put(&vlan->refcount, batadv_softif_vlan_release);
 514 }
 515
 516 /**
 517  * batadv_softif_vlan_get - get the vlan object for a specific vid
 518  * @bat_priv: the bat priv with all the soft interface information
 519  * @vid: the identifier of the vlan object to retrieve
 520  *
 521  * Return: the private data of the vlan matching the vid passed as argument or
 522  * NULL otherwise. The refcounter of the returned object is incremented by 1.
 523  */
 524 struct batadv_softif_vlan *batadv_softif_vlan_get(struct batadv_priv *bat_priv,
 525                                                   unsigned short vid)
 526 {
 527         struct batadv_softif_vlan *vlan_tmp, *vlan = NULL;
 528
 529         rcu_read_lock();
 530         hlist_for_each_entry_rcu(vlan_tmp, &bat_priv->softif_vlan_list, list) {
 531                 if (vlan_tmp->vid != vid)
 532                         continue;
 533
 534                 if (!kref_get_unless_zero(&vlan_tmp->refcount))
 535                         continue;
 536
 537                 vlan = vlan_tmp;
 538                 break;
 539         }
 540         rcu_read_unlock();
 541
 542         return vlan;
 543 }
 544
 545 /**
 546  * batadv_create_vlan - allocate the needed resources for a new vlan
 547  * @bat_priv: the bat priv with all the soft interface information
 548  * @vid: the VLAN identifier
 549  *
 550  * Return: 0 on success, a negative error otherwise.
 551  */
 552 int batadv_softif_create_vlan(struct batadv_priv *bat_priv, unsigned short vid)
 553 {
 554         struct batadv_softif_vlan *vlan;
 555         int err;
 556
 557         vlan = batadv_softif_vlan_get(bat_priv, vid);
 558         if (vlan) {
 559                 batadv_softif_vlan_put(vlan);
 560                 return -EEXIST;
 561         }
 562
 563         vlan = kzalloc(sizeof(*vlan), GFP_ATOMIC);
 564         if (!vlan)
 565                 return -ENOMEM;
 566
 567         vlan->bat_priv = bat_priv;
 568         vlan->vid = vid;
 569         kref_init(&vlan->refcount);
 570
 571         atomic_set(&vlan->ap_isolation, 0);
 572
 573         err = batadv_sysfs_add_vlan(bat_priv->soft_iface, vlan);
 574         if (err) {
 575                 kfree(vlan);
 576                 return err;
 577         }
 578
 579         spin_lock_bh(&bat_priv->softif_vlan_list_lock);
 580         hlist_add_head_rcu(&vlan->list, &bat_priv->softif_vlan_list);
 581         spin_unlock_bh(&bat_priv->softif_vlan_list_lock);
 582
 583         /* add a new TT local entry. This one will be marked with the NOPURGE
 584          * flag
 585          */
 586         batadv_tt_local_add(bat_priv->soft_iface,
 587                             bat_priv->soft_iface->dev_addr, vid,
 588                             BATADV_NULL_IFINDEX, BATADV_NO_MARK);
 589
 590         return 0;
 591 }
 592
 593 /**
 594  * batadv_softif_destroy_vlan - remove and destroy a softif_vlan object
 595  * @bat_priv: the bat priv with all the soft interface information
 596  * @vlan: the object to remove
 597  */
 598 static void batadv_softif_destroy_vlan(struct batadv_priv *bat_priv,
 599                                        struct batadv_softif_vlan *vlan)
 600 {
 601         /* explicitly remove the associated TT local entry because it is marked
 602          * with the NOPURGE flag
 603          */
 604         batadv_tt_local_remove(bat_priv, bat_priv->soft_iface->dev_addr,
 605                                vlan->vid, "vlan interface destroyed", false);
 606
 607         batadv_sysfs_del_vlan(bat_priv, vlan);
 608         batadv_softif_vlan_put(vlan);
 609 }
 610
 611 /**
 612  * batadv_interface_add_vid - ndo_add_vid API implementation
 613  * @dev: the netdev of the mesh interface
 614  * @proto: protocol of the the vlan id
 615  * @vid: identifier of the new vlan
 616  *
 617  * Set up all the internal structures for handling the new vlan on top of the
 618  * mesh interface
 619  *
 620  * Return: 0 on success or a negative error code in case of failure.
 621  */
 622 static int batadv_interface_add_vid(struct net_device *dev, __be16 proto,
 623                                     unsigned short vid)
 624 {
 625         struct batadv_priv *bat_priv = netdev_priv(dev);
 626         struct batadv_softif_vlan *vlan;
 627         int ret;
 628
 629         /* only 802.1Q vlans are supported.
 630          * batman-adv does not know how to handle other types
 631          */
 632         if (proto != htons(ETH_P_8021Q))
 633                 return -EINVAL;
 634
 635         vid |= BATADV_VLAN_HAS_TAG;
 636
 637         /* if a new vlan is getting created and it already exists, it means that
 638          * it was not deleted yet. batadv_softif_vlan_get() increases the
 639          * refcount in order to revive the object.
 640          *
 641          * if it does not exist then create it.
 642          */
 643         vlan = batadv_softif_vlan_get(bat_priv, vid);
 644         if (!vlan)
 645                 return batadv_softif_create_vlan(bat_priv, vid);
 646
 647         /* recreate the sysfs object if it was already destroyed (and it should
 648          * be since we received a kill_vid() for this vlan
 649          */
 650         if (!vlan->kobj) {
 651                 ret = batadv_sysfs_add_vlan(bat_priv->soft_iface, vlan);
 652                 if (ret) {
 653                         batadv_softif_vlan_put(vlan);
 654                         return ret;
 655                 }
 656         }
 657
 658         /* add a new TT local entry. This one will be marked with the NOPURGE
 659          * flag. This must be added again, even if the vlan object already
 660          * exists, because the entry was deleted by kill_vid()
 661          */
 662         batadv_tt_local_add(bat_priv->soft_iface,
 663                             bat_priv->soft_iface->dev_addr, vid,
 664                             BATADV_NULL_IFINDEX, BATADV_NO_MARK);
 665
 666         return 0;
 667 }
 668
 669 /**
 670  * batadv_interface_kill_vid - ndo_kill_vid API implementation
 671  * @dev: the netdev of the mesh interface
 672  * @proto: protocol of the the vlan id
 673  * @vid: identifier of the deleted vlan
 674  *
 675  * Destroy all the internal structures used to handle the vlan identified by vid
 676  * on top of the mesh interface
 677  *
 678  * Return: 0 on success, -EINVAL if the specified prototype is not ETH_P_8021Q
 679  * or -ENOENT if the specified vlan id wasn't registered.
 680  */
 681 static int batadv_interface_kill_vid(struct net_device *dev, __be16 proto,
 682                                      unsigned short vid)
 683 {
 684         struct batadv_priv *bat_priv = netdev_priv(dev);
 685         struct batadv_softif_vlan *vlan;
 686
 687         /* only 802.1Q vlans are supported. batman-adv does not know how to
 688          * handle other types
 689          */
 690         if (proto != htons(ETH_P_8021Q))
 691                 return -EINVAL;
 692
 693         vlan = batadv_softif_vlan_get(bat_priv, vid | BATADV_VLAN_HAS_TAG);
 694         if (!vlan)
 695                 return -ENOENT;
 696
 697         batadv_softif_destroy_vlan(bat_priv, vlan);
 698
 699         /* finally free the vlan object */
 700         batadv_softif_vlan_put(vlan);
 701
 702         return 0;
 703 }
 704
 705 /* batman-adv network devices have devices nesting below it and are a special
 706  * "super class" of normal network devices; split their locks off into a
 707  * separate class since they always nest.
 708  */
 709 static struct lock_class_key batadv_netdev_xmit_lock_key;
 710 static struct lock_class_key batadv_netdev_addr_lock_key;
 711
 712 /**
 713  * batadv_set_lockdep_class_one - Set lockdep class for a single tx queue
 714  * @dev: device which owns the tx queue
 715  * @txq: tx queue to modify
 716  * @_unused: always NULL
 717  */
 718 static void batadv_set_lockdep_class_one(struct net_device *dev,
 719                                          struct netdev_queue *txq,
 720                                          void *_unused)
 721 {
 722         lockdep_set_class(&txq->_xmit_lock, &batadv_netdev_xmit_lock_key);
 723 }
 724
 725 /**
 726  * batadv_set_lockdep_class - Set txq and addr_list lockdep class
 727  * @dev: network device to modify
 728  */
 729 static void batadv_set_lockdep_class(struct net_device *dev)
 730 {
 731         lockdep_set_class(&dev->addr_list_lock, &batadv_netdev_addr_lock_key);
 732         netdev_for_each_tx_queue(dev, batadv_set_lockdep_class_one, NULL);
 733 }
 734
 735 /**
 736  * batadv_softif_destroy_finish - cleans up the remains of a softif
 737  * @work: work queue item
 738  *
 739  * Free the parts of the soft interface which can not be removed under
 740  * rtnl lock (to prevent deadlock situations).
 741  */
 742 static void batadv_softif_destroy_finish(struct work_struct *work)
 743 {
 744         struct batadv_softif_vlan *vlan;
 745         struct batadv_priv *bat_priv;
 746         struct net_device *soft_iface;
 747
 748         bat_priv = container_of(work, struct batadv_priv,
 749                                 cleanup_work);
 750         soft_iface = bat_priv->soft_iface;
 751
 752         /* destroy the "untagged" VLAN */
 753         vlan = batadv_softif_vlan_get(bat_priv, BATADV_NO_FLAGS);
 754         if (vlan) {
 755                 batadv_softif_destroy_vlan(bat_priv, vlan);
 756                 batadv_softif_vlan_put(vlan);
 757         }
 758
 759         batadv_sysfs_del_meshif(soft_iface);
 760         unregister_netdev(soft_iface);
 761 }
 762
 763 /**
 764  * batadv_softif_init_late - late stage initialization of soft interface
 765  * @dev: registered network device to modify
 766  *
 767  * Return: error code on failures
 768  */
 769 static int batadv_softif_init_late(struct net_device *dev)
 770 {
 771         struct batadv_priv *bat_priv;
 772         u32 random_seqno;
 773         int ret;
 774         size_t cnt_len = sizeof(u64) * BATADV_CNT_NUM;
 775
 776         batadv_set_lockdep_class(dev);
 777
 778         bat_priv = netdev_priv(dev);
 779         bat_priv->soft_iface = dev;
 780         INIT_WORK(&bat_priv->cleanup_work, batadv_softif_destroy_finish);
 781
 782         /* batadv_interface_stats() needs to be available as soon as
 783          * register_netdevice() has been called
 784          */
 785         bat_priv->bat_counters = __alloc_percpu(cnt_len, __alignof__(u64));
 786         if (!bat_priv->bat_counters)
 787                 return -ENOMEM;
 788
 789         atomic_set(&bat_priv->aggregated_ogms, 1);
 790         atomic_set(&bat_priv->bonding, 0);
 791 #ifdef CONFIG_BATMAN_ADV_BLA
 792         atomic_set(&bat_priv->bridge_loop_avoidance, 1);
 793 #endif
 794 #ifdef CONFIG_BATMAN_ADV_DAT
 795         atomic_set(&bat_priv->distributed_arp_table, 1);
 796 #endif
 797 #ifdef CONFIG_BATMAN_ADV_MCAST
 798         bat_priv->mcast.flags = BATADV_NO_FLAGS;
 799         atomic_set(&bat_priv->multicast_mode, 1);
 800         atomic_set(&bat_priv->mcast.num_disabled, 0);
 801         atomic_set(&bat_priv->mcast.num_want_all_unsnoopables, 0);
 802         atomic_set(&bat_priv->mcast.num_want_all_ipv4, 0);
 803         atomic_set(&bat_priv->mcast.num_want_all_ipv6, 0);
 804 #endif
 805         atomic_set(&bat_priv->gw_mode, BATADV_GW_MODE_OFF);
 806         atomic_set(&bat_priv->gw_sel_class, 20);
 807         atomic_set(&bat_priv->gw.bandwidth_down, 100);
 808         atomic_set(&bat_priv->gw.bandwidth_up, 20);
 809         atomic_set(&bat_priv->orig_interval, 1000);
 810         atomic_set(&bat_priv->hop_penalty, 30);
 811 #ifdef CONFIG_BATMAN_ADV_DEBUG
 812         atomic_set(&bat_priv->log_level, 0);
 813 #endif
 814         atomic_set(&bat_priv->fragmentation, 1);
 815         atomic_set(&bat_priv->packet_size_max, ETH_DATA_LEN);
 816         atomic_set(&bat_priv->bcast_queue_left, BATADV_BCAST_QUEUE_LEN);
 817         atomic_set(&bat_priv->batman_queue_left, BATADV_BATMAN_QUEUE_LEN);
 818
 819         atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
 820         atomic_set(&bat_priv->bcast_seqno, 1);
 821         atomic_set(&bat_priv->tt.vn, 0);
 822         atomic_set(&bat_priv->tt.local_changes, 0);
 823         atomic_set(&bat_priv->tt.ogm_append_cnt, 0);
 824 #ifdef CONFIG_BATMAN_ADV_BLA
 825         atomic_set(&bat_priv->bla.num_requests, 0);
 826 #endif
 827         bat_priv->tt.last_changeset = NULL;
 828         bat_priv->tt.last_changeset_len = 0;
 829         bat_priv->isolation_mark = 0;
 830         bat_priv->isolation_mark_mask = 0;
 831
 832         /* randomize initial seqno to avoid collision */
 833         get_random_bytes(&random_seqno, sizeof(random_seqno));
 834         atomic_set(&bat_priv->frag_seqno, random_seqno);
 835
 836         bat_priv->primary_if = NULL;
 837         bat_priv->num_ifaces = 0;
 838
 839         batadv_nc_init_bat_priv(bat_priv);
 840
 841         ret = batadv_algo_select(bat_priv, batadv_routing_algo);
 842         if (ret < 0)
 843                 goto free_bat_counters;
 844
 845         ret = batadv_debugfs_add_meshif(dev);
 846         if (ret < 0)
 847                 goto free_bat_counters;
 848
 849         ret = batadv_mesh_init(dev);
 850         if (ret < 0)
 851                 goto unreg_debugfs;
 852
 853         return 0;
 854
 855 unreg_debugfs:
 856         batadv_debugfs_del_meshif(dev);
 857 free_bat_counters:
 858         free_percpu(bat_priv->bat_counters);
 859         bat_priv->bat_counters = NULL;
 860
 861         return ret;
 862 }
 863
 864 /**
 865  * batadv_softif_slave_add - Add a slave interface to a batadv_soft_interface
 866  * @dev: batadv_soft_interface used as master interface
 867  * @slave_dev: net_device which should become the slave interface
 868  *
 869  * Return: 0 if successful or error otherwise.
 870  */
 871 static int batadv_softif_slave_add(struct net_device *dev,
 872                                    struct net_device *slave_dev)
 873 {
 874         struct batadv_hard_iface *hard_iface;
 875         int ret = -EINVAL;
 876
 877         hard_iface = batadv_hardif_get_by_netdev(slave_dev);
 878         if (!hard_iface || hard_iface->soft_iface)
 879                 goto out;
 880
 881         ret = batadv_hardif_enable_interface(hard_iface, dev->name);
 882
 883 out:
 884         if (hard_iface)
 885                 batadv_hardif_put(hard_iface);
 886         return ret;
 887 }
 888
 889 /**
 890  * batadv_softif_slave_del - Delete a slave iface from a batadv_soft_interface
 891  * @dev: batadv_soft_interface used as master interface
 892  * @slave_dev: net_device which should be removed from the master interface
 893  *
 894  * Return: 0 if successful or error otherwise.
 895  */
 896 static int batadv_softif_slave_del(struct net_device *dev,
 897                                    struct net_device *slave_dev)
 898 {
 899         struct batadv_hard_iface *hard_iface;
 900         int ret = -EINVAL;
 901
 902         hard_iface = batadv_hardif_get_by_netdev(slave_dev);
 903
 904         if (!hard_iface || hard_iface->soft_iface != dev)
 905                 goto out;
 906
 907         batadv_hardif_disable_interface(hard_iface, BATADV_IF_CLEANUP_KEEP);
 908         ret = 0;
 909
 910 out:
 911         if (hard_iface)
 912                 batadv_hardif_put(hard_iface);
 913         return ret;
 914 }
 915
 916 static const struct net_device_ops batadv_netdev_ops = {
 917         .ndo_init = batadv_softif_init_late,
 918         .ndo_open = batadv_interface_open,
 919         .ndo_stop = batadv_interface_release,
 920         .ndo_get_stats = batadv_interface_stats,
 921         .ndo_vlan_rx_add_vid = batadv_interface_add_vid,
 922         .ndo_vlan_rx_kill_vid = batadv_interface_kill_vid,
 923         .ndo_set_mac_address = batadv_interface_set_mac_addr,
 924         .ndo_change_mtu = batadv_interface_change_mtu,
 925         .ndo_set_rx_mode = batadv_interface_set_rx_mode,
 926         .ndo_start_xmit = batadv_interface_tx,
 927         .ndo_validate_addr = eth_validate_addr,
 928         .ndo_add_slave = batadv_softif_slave_add,
 929         .ndo_del_slave = batadv_softif_slave_del,
 930 };
 931
 932 /**
 933  * batadv_softif_free - Deconstructor of batadv_soft_interface
 934  * @dev: Device to cleanup and remove
 935  */
 936 static void batadv_softif_free(struct net_device *dev)
 937 {
 938         batadv_debugfs_del_meshif(dev);
 939         batadv_mesh_free(dev);
 940
 941         /* some scheduled RCU callbacks need the bat_priv struct to accomplish
 942          * their tasks. Wait for them all to be finished before freeing the
 943          * netdev and its private data (bat_priv)
 944          */
 945         rcu_barrier();
 946
 947         free_netdev(dev);
 948 }
 949
 950 /**
 951  * batadv_softif_init_early - early stage initialization of soft interface
 952  * @dev: registered network device to modify
 953  */
 954 static void batadv_softif_init_early(struct net_device *dev)
 955 {
 956         struct batadv_priv *priv = netdev_priv(dev);
 957
 958         ether_setup(dev);
 959
 960         dev->netdev_ops = &batadv_netdev_ops;
 961         dev->destructor = batadv_softif_free;
 962         dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
 963         dev->priv_flags |= IFF_NO_QUEUE;
 964
 965         /* can't call min_mtu, because the needed variables
 966          * have not been initialized yet
 967          */
 968         dev->mtu = ETH_DATA_LEN;
 969
 970         /* generate random address */
 971         eth_hw_addr_random(dev);
 972
 973         dev->ethtool_ops = &batadv_ethtool_ops;
 974
 975         memset(priv, 0, sizeof(*priv));
 976 }
 977
 978 struct net_device *batadv_softif_create(const char *name)
 979 {
 980         struct net_device *soft_iface;
 981         int ret;
 982
 983         soft_iface = alloc_netdev(sizeof(struct batadv_priv), name,
 984                                   NET_NAME_UNKNOWN, batadv_softif_init_early);
 985         if (!soft_iface)
 986                 return NULL;
 987
 988         soft_iface->rtnl_link_ops = &batadv_link_ops;
 989
 990         ret = register_netdevice(soft_iface);
 991         if (ret < 0) {
 992                 pr_err("Unable to register the batman interface '%s': %i\n",
 993                        name, ret);
 994                 free_netdev(soft_iface);
 995                 return NULL;
 996         }
 997
 998         return soft_iface;
 999 }
1000
1001 /**
1002  * batadv_softif_destroy_sysfs - deletion of batadv_soft_interface via sysfs
1003  * @soft_iface: the to-be-removed batman-adv interface
1004  */
1005 void batadv_softif_destroy_sysfs(struct net_device *soft_iface)
1006 {
1007         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
1008
1009         queue_work(batadv_event_workqueue, &bat_priv->cleanup_work);
1010 }
1011
1012 /**
1013  * batadv_softif_destroy_netlink - deletion of batadv_soft_interface via netlink
1014  * @soft_iface: the to-be-removed batman-adv interface
1015  * @head: list pointer
1016  */
1017 static void batadv_softif_destroy_netlink(struct net_device *soft_iface,
1018                                           struct list_head *head)
1019 {
1020         struct batadv_hard_iface *hard_iface;
1021
1022         list_for_each_entry(hard_iface, &batadv_hardif_list, list) {
1023                 if (hard_iface->soft_iface == soft_iface)
1024                         batadv_hardif_disable_interface(hard_iface,
1025                                                         BATADV_IF_CLEANUP_KEEP);
1026         }
1027
1028         batadv_sysfs_del_meshif(soft_iface);
1029         unregister_netdevice_queue(soft_iface, head);
1030 }
1031
1032 int batadv_softif_is_valid(const struct net_device *net_dev)
1033 {
1034         if (net_dev->netdev_ops->ndo_start_xmit == batadv_interface_tx)
1035                 return 1;
1036
1037         return 0;
1038 }
1039
1040 struct rtnl_link_ops batadv_link_ops __read_mostly = {
1041         .kind           = "batadv",
1042         .priv_size      = sizeof(struct batadv_priv),
1043         .setup          = batadv_softif_init_early,
1044         .dellink        = batadv_softif_destroy_netlink,
1045 };
1046
1047 /* ethtool */
1048 static int batadv_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1049 {
1050         cmd->supported = 0;
1051         cmd->advertising = 0;
1052         ethtool_cmd_speed_set(cmd, SPEED_10);
1053         cmd->duplex = DUPLEX_FULL;
1054         cmd->port = PORT_TP;
1055         cmd->phy_address = 0;
1056         cmd->transceiver = XCVR_INTERNAL;
1057         cmd->autoneg = AUTONEG_DISABLE;
1058         cmd->maxtxpkt = 0;
1059         cmd->maxrxpkt = 0;
1060
1061         return 0;
1062 }
1063
1064 static void batadv_get_drvinfo(struct net_device *dev,
1065                                struct ethtool_drvinfo *info)
1066 {
1067         strlcpy(info->driver, "B.A.T.M.A.N. advanced", sizeof(info->driver));
1068         strlcpy(info->version, BATADV_SOURCE_VERSION, sizeof(info->version));
1069         strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
1070         strlcpy(info->bus_info, "batman", sizeof(info->bus_info));
1071 }
1072
1073 static u32 batadv_get_msglevel(struct net_device *dev)
1074 {
1075         return -EOPNOTSUPP;
1076 }
1077
1078 static void batadv_set_msglevel(struct net_device *dev, u32 value)
1079 {
1080 }
1081
1082 static u32 batadv_get_link(struct net_device *dev)
1083 {
1084         return 1;
1085 }
1086
1087 /* Inspired by drivers/net/ethernet/dlink/sundance.c:1702
1088  * Declare each description string in struct.name[] to get fixed sized buffer
1089  * and compile time checking for strings longer than ETH_GSTRING_LEN.
1090  */
1091 static const struct {
1092         const char name[ETH_GSTRING_LEN];
1093 } batadv_counters_strings[] = {
1094         { "tx" },
1095         { "tx_bytes" },
1096         { "tx_dropped" },
1097         { "rx" },
1098         { "rx_bytes" },
1099         { "forward" },
1100         { "forward_bytes" },
1101         { "mgmt_tx" },
1102         { "mgmt_tx_bytes" },
1103         { "mgmt_rx" },
1104         { "mgmt_rx_bytes" },
1105         { "frag_tx" },
1106         { "frag_tx_bytes" },
1107         { "frag_rx" },
1108         { "frag_rx_bytes" },
1109         { "frag_fwd" },
1110         { "frag_fwd_bytes" },
1111         { "tt_request_tx" },
1112         { "tt_request_rx" },
1113         { "tt_response_tx" },
1114         { "tt_response_rx" },
1115         { "tt_roam_adv_tx" },
1116         { "tt_roam_adv_rx" },
1117 #ifdef CONFIG_BATMAN_ADV_DAT
1118         { "dat_get_tx" },
1119         { "dat_get_rx" },
1120         { "dat_put_tx" },
1121         { "dat_put_rx" },
1122         { "dat_cached_reply_tx" },
1123 #endif
1124 #ifdef CONFIG_BATMAN_ADV_NC
1125         { "nc_code" },
1126         { "nc_code_bytes" },
1127         { "nc_recode" },
1128         { "nc_recode_bytes" },
1129         { "nc_buffer" },
1130         { "nc_decode" },
1131         { "nc_decode_bytes" },
1132         { "nc_decode_failed" },
1133         { "nc_sniffed" },
1134 #endif
1135 };
1136
1137 static void batadv_get_strings(struct net_device *dev, u32 stringset, u8 *data)
1138 {
1139         if (stringset == ETH_SS_STATS)
1140                 memcpy(data, batadv_counters_strings,
1141                        sizeof(batadv_counters_strings));
1142 }
1143
1144 static void batadv_get_ethtool_stats(struct net_device *dev,
1145                                      struct ethtool_stats *stats, u64 *data)
1146 {
1147         struct batadv_priv *bat_priv = netdev_priv(dev);
1148         int i;
1149
1150         for (i = 0; i < BATADV_CNT_NUM; i++)
1151                 data[i] = batadv_sum_counter(bat_priv, i);
1152 }
1153
1154 static int batadv_get_sset_count(struct net_device *dev, int stringset)
1155 {
1156         if (stringset == ETH_SS_STATS)
1157                 return BATADV_CNT_NUM;
1158
1159         return -EOPNOTSUPP;
1160 }