net/batman-adv/main.c

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
batadv_init
batadv_exit
batadv_mesh_init
batadv_mesh_free
batadv_is_my_mac
batadv_seq_print_text_primary_if_get
batadv_max_header_len
batadv_skb_set_priority
batadv_recv_unhandled_packet
batadv_batman_skb_recv
batadv_recv_handler_init
batadv_recv_handler_register
batadv_recv_handler_unregister
batadv_skb_crc32
batadv_get_vid
batadv_vlan_ap_isola_get
batadv_throw_uevent
   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (C) 2007-2019  B.A.T.M.A.N. contributors:
   3  *
   4  * Marek Lindner, Simon Wunderlich
   5  */
   6 
   7 #include "main.h"
   8 
   9 #include <linux/atomic.h>
  10 #include <linux/build_bug.h>
  11 #include <linux/byteorder/generic.h>
  12 #include <linux/crc32c.h>
  13 #include <linux/device.h>
  14 #include <linux/errno.h>
  15 #include <linux/genetlink.h>
  16 #include <linux/gfp.h>
  17 #include <linux/if_ether.h>
  18 #include <linux/if_vlan.h>
  19 #include <linux/init.h>
  20 #include <linux/ip.h>
  21 #include <linux/ipv6.h>
  22 #include <linux/kernel.h>
  23 #include <linux/kobject.h>
  24 #include <linux/kref.h>
  25 #include <linux/list.h>
  26 #include <linux/module.h>
  27 #include <linux/netdevice.h>
  28 #include <linux/printk.h>
  29 #include <linux/rculist.h>
  30 #include <linux/rcupdate.h>
  31 #include <linux/seq_file.h>
  32 #include <linux/skbuff.h>
  33 #include <linux/slab.h>
  34 #include <linux/spinlock.h>
  35 #include <linux/stddef.h>
  36 #include <linux/string.h>
  37 #include <linux/workqueue.h>
  38 #include <net/dsfield.h>
  39 #include <net/rtnetlink.h>
  40 #include <uapi/linux/batadv_packet.h>
  41 #include <uapi/linux/batman_adv.h>
  42 
  43 #include "bat_algo.h"
  44 #include "bat_iv_ogm.h"
  45 #include "bat_v.h"
  46 #include "bridge_loop_avoidance.h"
  47 #include "debugfs.h"
  48 #include "distributed-arp-table.h"
  49 #include "gateway_client.h"
  50 #include "gateway_common.h"
  51 #include "hard-interface.h"
  52 #include "icmp_socket.h"
  53 #include "log.h"
  54 #include "multicast.h"
  55 #include "netlink.h"
  56 #include "network-coding.h"
  57 #include "originator.h"
  58 #include "routing.h"
  59 #include "send.h"
  60 #include "soft-interface.h"
  61 #include "tp_meter.h"
  62 #include "translation-table.h"
  63 
  64 /* List manipulations on hardif_list have to be rtnl_lock()'ed,
  65  * list traversals just rcu-locked
  66  */
  67 struct list_head batadv_hardif_list;
  68 unsigned int batadv_hardif_generation;
  69 static int (*batadv_rx_handler[256])(struct sk_buff *skb,
  70                                      struct batadv_hard_iface *recv_if);
  71 
  72 unsigned char batadv_broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
  73 
  74 struct workqueue_struct *batadv_event_workqueue;
  75 
  76 static void batadv_recv_handler_init(void);
  77 
  78 #define BATADV_UEV_TYPE_VAR     "BATTYPE="
  79 #define BATADV_UEV_ACTION_VAR   "BATACTION="
  80 #define BATADV_UEV_DATA_VAR     "BATDATA="
  81 
  82 static char *batadv_uev_action_str[] = {
  83         "add",
  84         "del",
  85         "change",
  86         "loopdetect",
  87 };
  88 
  89 static char *batadv_uev_type_str[] = {
  90         "gw",
  91         "bla",
  92 };
  93 
  94 static int __init batadv_init(void)
  95 {
  96         int ret;
  97 
  98         ret = batadv_tt_cache_init();
  99         if (ret < 0)
 100                 return ret;
 101 
 102         INIT_LIST_HEAD(&batadv_hardif_list);
 103         batadv_algo_init();
 104 
 105         batadv_recv_handler_init();
 106 
 107         batadv_v_init();
 108         batadv_iv_init();
 109         batadv_nc_init();
 110         batadv_tp_meter_init();
 111 
 112         batadv_event_workqueue = create_singlethread_workqueue("bat_events");
 113         if (!batadv_event_workqueue)
 114                 goto err_create_wq;
 115 
 116         batadv_socket_init();
 117         batadv_debugfs_init();
 118 
 119         register_netdevice_notifier(&batadv_hard_if_notifier);
 120         rtnl_link_register(&batadv_link_ops);
 121         batadv_netlink_register();
 122 
 123         pr_info("B.A.T.M.A.N. advanced %s (compatibility version %i) loaded\n",
 124                 BATADV_SOURCE_VERSION, BATADV_COMPAT_VERSION);
 125 
 126         return 0;
 127 
 128 err_create_wq:
 129         batadv_tt_cache_destroy();
 130 
 131         return -ENOMEM;
 132 }
 133 
 134 static void __exit batadv_exit(void)
 135 {
 136         batadv_debugfs_destroy();
 137         batadv_netlink_unregister();
 138         rtnl_link_unregister(&batadv_link_ops);
 139         unregister_netdevice_notifier(&batadv_hard_if_notifier);
 140         batadv_hardif_remove_interfaces();
 141 
 142         flush_workqueue(batadv_event_workqueue);
 143         destroy_workqueue(batadv_event_workqueue);
 144         batadv_event_workqueue = NULL;
 145 
 146         rcu_barrier();
 147 
 148         batadv_tt_cache_destroy();
 149 }
 150 
 151 /**
 152  * batadv_mesh_init() - Initialize soft interface
 153  * @soft_iface: netdev struct of the soft interface
 154  *
 155  * Return: 0 on success or negative error number in case of failure
 156  */
 157 int batadv_mesh_init(struct net_device *soft_iface)
 158 {
 159         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 160         int ret;
 161 
 162         spin_lock_init(&bat_priv->forw_bat_list_lock);
 163         spin_lock_init(&bat_priv->forw_bcast_list_lock);
 164         spin_lock_init(&bat_priv->tt.changes_list_lock);
 165         spin_lock_init(&bat_priv->tt.req_list_lock);
 166         spin_lock_init(&bat_priv->tt.roam_list_lock);
 167         spin_lock_init(&bat_priv->tt.last_changeset_lock);
 168         spin_lock_init(&bat_priv->tt.commit_lock);
 169         spin_lock_init(&bat_priv->gw.list_lock);
 170 #ifdef CONFIG_BATMAN_ADV_MCAST
 171         spin_lock_init(&bat_priv->mcast.mla_lock);
 172         spin_lock_init(&bat_priv->mcast.want_lists_lock);
 173 #endif
 174         spin_lock_init(&bat_priv->tvlv.container_list_lock);
 175         spin_lock_init(&bat_priv->tvlv.handler_list_lock);
 176         spin_lock_init(&bat_priv->softif_vlan_list_lock);
 177         spin_lock_init(&bat_priv->tp_list_lock);
 178 
 179         INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
 180         INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
 181         INIT_HLIST_HEAD(&bat_priv->gw.gateway_list);
 182 #ifdef CONFIG_BATMAN_ADV_MCAST
 183         INIT_HLIST_HEAD(&bat_priv->mcast.want_all_unsnoopables_list);
 184         INIT_HLIST_HEAD(&bat_priv->mcast.want_all_ipv4_list);
 185         INIT_HLIST_HEAD(&bat_priv->mcast.want_all_ipv6_list);
 186 #endif
 187         INIT_LIST_HEAD(&bat_priv->tt.changes_list);
 188         INIT_HLIST_HEAD(&bat_priv->tt.req_list);
 189         INIT_LIST_HEAD(&bat_priv->tt.roam_list);
 190 #ifdef CONFIG_BATMAN_ADV_MCAST
 191         INIT_HLIST_HEAD(&bat_priv->mcast.mla_list);
 192 #endif
 193         INIT_HLIST_HEAD(&bat_priv->tvlv.container_list);
 194         INIT_HLIST_HEAD(&bat_priv->tvlv.handler_list);
 195         INIT_HLIST_HEAD(&bat_priv->softif_vlan_list);
 196         INIT_HLIST_HEAD(&bat_priv->tp_list);
 197 
 198         bat_priv->gw.generation = 0;
 199 
 200         ret = batadv_v_mesh_init(bat_priv);
 201         if (ret < 0)
 202                 goto err;
 203 
 204         ret = batadv_originator_init(bat_priv);
 205         if (ret < 0)
 206                 goto err;
 207 
 208         ret = batadv_tt_init(bat_priv);
 209         if (ret < 0)
 210                 goto err;
 211 
 212         ret = batadv_bla_init(bat_priv);
 213         if (ret < 0)
 214                 goto err;
 215 
 216         ret = batadv_dat_init(bat_priv);
 217         if (ret < 0)
 218                 goto err;
 219 
 220         ret = batadv_nc_mesh_init(bat_priv);
 221         if (ret < 0)
 222                 goto err;
 223 
 224         batadv_gw_init(bat_priv);
 225         batadv_mcast_init(bat_priv);
 226 
 227         atomic_set(&bat_priv->gw.reselect, 0);
 228         atomic_set(&bat_priv->mesh_state, BATADV_MESH_ACTIVE);
 229 
 230         return 0;
 231 
 232 err:
 233         batadv_mesh_free(soft_iface);
 234         return ret;
 235 }
 236 
 237 /**
 238  * batadv_mesh_free() - Deinitialize soft interface
 239  * @soft_iface: netdev struct of the soft interface
 240  */
 241 void batadv_mesh_free(struct net_device *soft_iface)
 242 {
 243         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 244 
 245         atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);
 246 
 247         batadv_purge_outstanding_packets(bat_priv, NULL);
 248 
 249         batadv_gw_node_free(bat_priv);
 250 
 251         batadv_v_mesh_free(bat_priv);
 252         batadv_nc_mesh_free(bat_priv);
 253         batadv_dat_free(bat_priv);
 254         batadv_bla_free(bat_priv);
 255 
 256         batadv_mcast_free(bat_priv);
 257 
 258         /* Free the TT and the originator tables only after having terminated
 259          * all the other depending components which may use these structures for
 260          * their purposes.
 261          */
 262         batadv_tt_free(bat_priv);
 263 
 264         /* Since the originator table clean up routine is accessing the TT
 265          * tables as well, it has to be invoked after the TT tables have been
 266          * freed and marked as empty. This ensures that no cleanup RCU callbacks
 267          * accessing the TT data are scheduled for later execution.
 268          */
 269         batadv_originator_free(bat_priv);
 270 
 271         batadv_gw_free(bat_priv);
 272 
 273         free_percpu(bat_priv->bat_counters);
 274         bat_priv->bat_counters = NULL;
 275 
 276         atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
 277 }
 278 
 279 /**
 280  * batadv_is_my_mac() - check if the given mac address belongs to any of the
 281  *  real interfaces in the current mesh
 282  * @bat_priv: the bat priv with all the soft interface information
 283  * @addr: the address to check
 284  *
 285  * Return: 'true' if the mac address was found, false otherwise.
 286  */
 287 bool batadv_is_my_mac(struct batadv_priv *bat_priv, const u8 *addr)
 288 {
 289         const struct batadv_hard_iface *hard_iface;
 290         bool is_my_mac = false;
 291 
 292         rcu_read_lock();
 293         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 294                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
 295                         continue;
 296 
 297                 if (hard_iface->soft_iface != bat_priv->soft_iface)
 298                         continue;
 299 
 300                 if (batadv_compare_eth(hard_iface->net_dev->dev_addr, addr)) {
 301                         is_my_mac = true;
 302                         break;
 303                 }
 304         }
 305         rcu_read_unlock();
 306         return is_my_mac;
 307 }
 308 
 309 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
 310 /**
 311  * batadv_seq_print_text_primary_if_get() - called from debugfs table printing
 312  *  function that requires the primary interface
 313  * @seq: debugfs table seq_file struct
 314  *
 315  * Return: primary interface if found or NULL otherwise.
 316  */
 317 struct batadv_hard_iface *
 318 batadv_seq_print_text_primary_if_get(struct seq_file *seq)
 319 {
 320         struct net_device *net_dev = (struct net_device *)seq->private;
 321         struct batadv_priv *bat_priv = netdev_priv(net_dev);
 322         struct batadv_hard_iface *primary_if;
 323 
 324         primary_if = batadv_primary_if_get_selected(bat_priv);
 325 
 326         if (!primary_if) {
 327                 seq_printf(seq,
 328                            "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
 329                            net_dev->name);
 330                 goto out;
 331         }
 332 
 333         if (primary_if->if_status == BATADV_IF_ACTIVE)
 334                 goto out;
 335 
 336         seq_printf(seq,
 337                    "BATMAN mesh %s disabled - primary interface not active\n",
 338                    net_dev->name);
 339         batadv_hardif_put(primary_if);
 340         primary_if = NULL;
 341 
 342 out:
 343         return primary_if;
 344 }
 345 #endif
 346 
 347 /**
 348  * batadv_max_header_len() - calculate maximum encapsulation overhead for a
 349  *  payload packet
 350  *
 351  * Return: the maximum encapsulation overhead in bytes.
 352  */
 353 int batadv_max_header_len(void)
 354 {
 355         int header_len = 0;
 356 
 357         header_len = max_t(int, header_len,
 358                            sizeof(struct batadv_unicast_packet));
 359         header_len = max_t(int, header_len,
 360                            sizeof(struct batadv_unicast_4addr_packet));
 361         header_len = max_t(int, header_len,
 362                            sizeof(struct batadv_bcast_packet));
 363 
 364 #ifdef CONFIG_BATMAN_ADV_NC
 365         header_len = max_t(int, header_len,
 366                            sizeof(struct batadv_coded_packet));
 367 #endif
 368 
 369         return header_len + ETH_HLEN;
 370 }
 371 
 372 /**
 373  * batadv_skb_set_priority() - sets skb priority according to packet content
 374  * @skb: the packet to be sent
 375  * @offset: offset to the packet content
 376  *
 377  * This function sets a value between 256 and 263 (802.1d priority), which
 378  * can be interpreted by the cfg80211 or other drivers.
 379  */
 380 void batadv_skb_set_priority(struct sk_buff *skb, int offset)
 381 {
 382         struct iphdr ip_hdr_tmp, *ip_hdr;
 383         struct ipv6hdr ip6_hdr_tmp, *ip6_hdr;
 384         struct ethhdr ethhdr_tmp, *ethhdr;
 385         struct vlan_ethhdr *vhdr, vhdr_tmp;
 386         u32 prio;
 387 
 388         /* already set, do nothing */
 389         if (skb->priority >= 256 && skb->priority <= 263)
 390                 return;
 391 
 392         ethhdr = skb_header_pointer(skb, offset, sizeof(*ethhdr), &ethhdr_tmp);
 393         if (!ethhdr)
 394                 return;
 395 
 396         switch (ethhdr->h_proto) {
 397         case htons(ETH_P_8021Q):
 398                 vhdr = skb_header_pointer(skb, offset + sizeof(*vhdr),
 399                                           sizeof(*vhdr), &vhdr_tmp);
 400                 if (!vhdr)
 401                         return;
 402                 prio = ntohs(vhdr->h_vlan_TCI) & VLAN_PRIO_MASK;
 403                 prio = prio >> VLAN_PRIO_SHIFT;
 404                 break;
 405         case htons(ETH_P_IP):
 406                 ip_hdr = skb_header_pointer(skb, offset + sizeof(*ethhdr),
 407                                             sizeof(*ip_hdr), &ip_hdr_tmp);
 408                 if (!ip_hdr)
 409                         return;
 410                 prio = (ipv4_get_dsfield(ip_hdr) & 0xfc) >> 5;
 411                 break;
 412         case htons(ETH_P_IPV6):
 413                 ip6_hdr = skb_header_pointer(skb, offset + sizeof(*ethhdr),
 414                                              sizeof(*ip6_hdr), &ip6_hdr_tmp);
 415                 if (!ip6_hdr)
 416                         return;
 417                 prio = (ipv6_get_dsfield(ip6_hdr) & 0xfc) >> 5;
 418                 break;
 419         default:
 420                 return;
 421         }
 422 
 423         skb->priority = prio + 256;
 424 }
 425 
 426 static int batadv_recv_unhandled_packet(struct sk_buff *skb,
 427                                         struct batadv_hard_iface *recv_if)
 428 {
 429         kfree_skb(skb);
 430 
 431         return NET_RX_DROP;
 432 }
 433 
 434 /* incoming packets with the batman ethertype received on any active hard
 435  * interface
 436  */
 437 
 438 /**
 439  * batadv_batman_skb_recv() - Handle incoming message from an hard interface
 440  * @skb: the received packet
 441  * @dev: the net device that the packet was received on
 442  * @ptype: packet type of incoming packet (ETH_P_BATMAN)
 443  * @orig_dev: the original receive net device (e.g. bonded device)
 444  *
 445  * Return: NET_RX_SUCCESS on success or NET_RX_DROP in case of failure
 446  */
 447 int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
 448                            struct packet_type *ptype,
 449                            struct net_device *orig_dev)
 450 {
 451         struct batadv_priv *bat_priv;
 452         struct batadv_ogm_packet *batadv_ogm_packet;
 453         struct batadv_hard_iface *hard_iface;
 454         u8 idx;
 455 
 456         hard_iface = container_of(ptype, struct batadv_hard_iface,
 457                                   batman_adv_ptype);
 458 
 459         /* Prevent processing a packet received on an interface which is getting
 460          * shut down otherwise the packet may trigger de-reference errors
 461          * further down in the receive path.
 462          */
 463         if (!kref_get_unless_zero(&hard_iface->refcount))
 464                 goto err_out;
 465 
 466         skb = skb_share_check(skb, GFP_ATOMIC);
 467 
 468         /* skb was released by skb_share_check() */
 469         if (!skb)
 470                 goto err_put;
 471 
 472         /* packet should hold at least type and version */
 473         if (unlikely(!pskb_may_pull(skb, 2)))
 474                 goto err_free;
 475 
 476         /* expect a valid ethernet header here. */
 477         if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb)))
 478                 goto err_free;
 479 
 480         if (!hard_iface->soft_iface)
 481                 goto err_free;
 482 
 483         bat_priv = netdev_priv(hard_iface->soft_iface);
 484 
 485         if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
 486                 goto err_free;
 487 
 488         /* discard frames on not active interfaces */
 489         if (hard_iface->if_status != BATADV_IF_ACTIVE)
 490                 goto err_free;
 491 
 492         batadv_ogm_packet = (struct batadv_ogm_packet *)skb->data;
 493 
 494         if (batadv_ogm_packet->version != BATADV_COMPAT_VERSION) {
 495                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 496                            "Drop packet: incompatible batman version (%i)\n",
 497                            batadv_ogm_packet->version);
 498                 goto err_free;
 499         }
 500 
 501         /* reset control block to avoid left overs from previous users */
 502         memset(skb->cb, 0, sizeof(struct batadv_skb_cb));
 503 
 504         idx = batadv_ogm_packet->packet_type;
 505         (*batadv_rx_handler[idx])(skb, hard_iface);
 506 
 507         batadv_hardif_put(hard_iface);
 508 
 509         /* return NET_RX_SUCCESS in any case as we
 510          * most probably dropped the packet for
 511          * routing-logical reasons.
 512          */
 513         return NET_RX_SUCCESS;
 514 
 515 err_free:
 516         kfree_skb(skb);
 517 err_put:
 518         batadv_hardif_put(hard_iface);
 519 err_out:
 520         return NET_RX_DROP;
 521 }
 522 
 523 static void batadv_recv_handler_init(void)
 524 {
 525         int i;
 526 
 527         for (i = 0; i < ARRAY_SIZE(batadv_rx_handler); i++)
 528                 batadv_rx_handler[i] = batadv_recv_unhandled_packet;
 529 
 530         for (i = BATADV_UNICAST_MIN; i <= BATADV_UNICAST_MAX; i++)
 531                 batadv_rx_handler[i] = batadv_recv_unhandled_unicast_packet;
 532 
 533         /* compile time checks for sizes */
 534         BUILD_BUG_ON(sizeof(struct batadv_bla_claim_dst) != 6);
 535         BUILD_BUG_ON(sizeof(struct batadv_ogm_packet) != 24);
 536         BUILD_BUG_ON(sizeof(struct batadv_icmp_header) != 20);
 537         BUILD_BUG_ON(sizeof(struct batadv_icmp_packet) != 20);
 538         BUILD_BUG_ON(sizeof(struct batadv_icmp_packet_rr) != 116);
 539         BUILD_BUG_ON(sizeof(struct batadv_unicast_packet) != 10);
 540         BUILD_BUG_ON(sizeof(struct batadv_unicast_4addr_packet) != 18);
 541         BUILD_BUG_ON(sizeof(struct batadv_frag_packet) != 20);
 542         BUILD_BUG_ON(sizeof(struct batadv_bcast_packet) != 14);
 543         BUILD_BUG_ON(sizeof(struct batadv_coded_packet) != 46);
 544         BUILD_BUG_ON(sizeof(struct batadv_unicast_tvlv_packet) != 20);
 545         BUILD_BUG_ON(sizeof(struct batadv_tvlv_hdr) != 4);
 546         BUILD_BUG_ON(sizeof(struct batadv_tvlv_gateway_data) != 8);
 547         BUILD_BUG_ON(sizeof(struct batadv_tvlv_tt_vlan_data) != 8);
 548         BUILD_BUG_ON(sizeof(struct batadv_tvlv_tt_change) != 12);
 549         BUILD_BUG_ON(sizeof(struct batadv_tvlv_roam_adv) != 8);
 550 
 551         i = FIELD_SIZEOF(struct sk_buff, cb);
 552         BUILD_BUG_ON(sizeof(struct batadv_skb_cb) > i);
 553 
 554         /* broadcast packet */
 555         batadv_rx_handler[BATADV_BCAST] = batadv_recv_bcast_packet;
 556 
 557         /* unicast packets ... */
 558         /* unicast with 4 addresses packet */
 559         batadv_rx_handler[BATADV_UNICAST_4ADDR] = batadv_recv_unicast_packet;
 560         /* unicast packet */
 561         batadv_rx_handler[BATADV_UNICAST] = batadv_recv_unicast_packet;
 562         /* unicast tvlv packet */
 563         batadv_rx_handler[BATADV_UNICAST_TVLV] = batadv_recv_unicast_tvlv;
 564         /* batman icmp packet */
 565         batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet;
 566         /* Fragmented packets */
 567         batadv_rx_handler[BATADV_UNICAST_FRAG] = batadv_recv_frag_packet;
 568 }
 569 
 570 /**
 571  * batadv_recv_handler_register() - Register handler for batman-adv packet type
 572  * @packet_type: batadv_packettype which should be handled
 573  * @recv_handler: receive handler for the packet type
 574  *
 575  * Return: 0 on success or negative error number in case of failure
 576  */
 577 int
 578 batadv_recv_handler_register(u8 packet_type,
 579                              int (*recv_handler)(struct sk_buff *,
 580                                                  struct batadv_hard_iface *))
 581 {
 582         int (*curr)(struct sk_buff *skb,
 583                     struct batadv_hard_iface *recv_if);
 584         curr = batadv_rx_handler[packet_type];
 585 
 586         if (curr != batadv_recv_unhandled_packet &&
 587             curr != batadv_recv_unhandled_unicast_packet)
 588                 return -EBUSY;
 589 
 590         batadv_rx_handler[packet_type] = recv_handler;
 591         return 0;
 592 }
 593 
 594 /**
 595  * batadv_recv_handler_unregister() - Unregister handler for packet type
 596  * @packet_type: batadv_packettype which should no longer be handled
 597  */
 598 void batadv_recv_handler_unregister(u8 packet_type)
 599 {
 600         batadv_rx_handler[packet_type] = batadv_recv_unhandled_packet;
 601 }
 602 
 603 /**
 604  * batadv_skb_crc32() - calculate CRC32 of the whole packet and skip bytes in
 605  *  the header
 606  * @skb: skb pointing to fragmented socket buffers
 607  * @payload_ptr: Pointer to position inside the head buffer of the skb
 608  *  marking the start of the data to be CRC'ed
 609  *
 610  * payload_ptr must always point to an address in the skb head buffer and not to
 611  * a fragment.
 612  *
 613  * Return: big endian crc32c of the checksummed data
 614  */
 615 __be32 batadv_skb_crc32(struct sk_buff *skb, u8 *payload_ptr)
 616 {
 617         u32 crc = 0;
 618         unsigned int from;
 619         unsigned int to = skb->len;
 620         struct skb_seq_state st;
 621         const u8 *data;
 622         unsigned int len;
 623         unsigned int consumed = 0;
 624 
 625         from = (unsigned int)(payload_ptr - skb->data);
 626 
 627         skb_prepare_seq_read(skb, from, to, &st);
 628         while ((len = skb_seq_read(consumed, &data, &st)) != 0) {
 629                 crc = crc32c(crc, data, len);
 630                 consumed += len;
 631         }
 632 
 633         return htonl(crc);
 634 }
 635 
 636 /**
 637  * batadv_get_vid() - extract the VLAN identifier from skb if any
 638  * @skb: the buffer containing the packet
 639  * @header_len: length of the batman header preceding the ethernet header
 640  *
 641  * Return: VID with the BATADV_VLAN_HAS_TAG flag when the packet embedded in the
 642  * skb is vlan tagged. Otherwise BATADV_NO_FLAGS.
 643  */
 644 unsigned short batadv_get_vid(struct sk_buff *skb, size_t header_len)
 645 {
 646         struct ethhdr *ethhdr = (struct ethhdr *)(skb->data + header_len);
 647         struct vlan_ethhdr *vhdr;
 648         unsigned short vid;
 649 
 650         if (ethhdr->h_proto != htons(ETH_P_8021Q))
 651                 return BATADV_NO_FLAGS;
 652 
 653         if (!pskb_may_pull(skb, header_len + VLAN_ETH_HLEN))
 654                 return BATADV_NO_FLAGS;
 655 
 656         vhdr = (struct vlan_ethhdr *)(skb->data + header_len);
 657         vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;
 658         vid |= BATADV_VLAN_HAS_TAG;
 659 
 660         return vid;
 661 }
 662 
 663 /**
 664  * batadv_vlan_ap_isola_get() - return AP isolation status for the given vlan
 665  * @bat_priv: the bat priv with all the soft interface information
 666  * @vid: the VLAN identifier for which the AP isolation attributed as to be
 667  *  looked up
 668  *
 669  * Return: true if AP isolation is on for the VLAN idenfied by vid, false
 670  * otherwise
 671  */
 672 bool batadv_vlan_ap_isola_get(struct batadv_priv *bat_priv, unsigned short vid)
 673 {
 674         bool ap_isolation_enabled = false;
 675         struct batadv_softif_vlan *vlan;
 676 
 677         /* if the AP isolation is requested on a VLAN, then check for its
 678          * setting in the proper VLAN private data structure
 679          */
 680         vlan = batadv_softif_vlan_get(bat_priv, vid);
 681         if (vlan) {
 682                 ap_isolation_enabled = atomic_read(&vlan->ap_isolation);
 683                 batadv_softif_vlan_put(vlan);
 684         }
 685 
 686         return ap_isolation_enabled;
 687 }
 688 
 689 /**
 690  * batadv_throw_uevent() - Send an uevent with batman-adv specific env data
 691  * @bat_priv: the bat priv with all the soft interface information
 692  * @type: subsystem type of event. Stored in uevent's BATTYPE
 693  * @action: action type of event. Stored in uevent's BATACTION
 694  * @data: string with additional information to the event (ignored for
 695  *  BATADV_UEV_DEL). Stored in uevent's BATDATA
 696  *
 697  * Return: 0 on success or negative error number in case of failure
 698  */
 699 int batadv_throw_uevent(struct batadv_priv *bat_priv, enum batadv_uev_type type,
 700                         enum batadv_uev_action action, const char *data)
 701 {
 702         int ret = -ENOMEM;
 703         struct kobject *bat_kobj;
 704         char *uevent_env[4] = { NULL, NULL, NULL, NULL };
 705 
 706         bat_kobj = &bat_priv->soft_iface->dev.kobj;
 707 
 708         uevent_env[0] = kasprintf(GFP_ATOMIC,
 709                                   "%s%s", BATADV_UEV_TYPE_VAR,
 710                                   batadv_uev_type_str[type]);
 711         if (!uevent_env[0])
 712                 goto out;
 713 
 714         uevent_env[1] = kasprintf(GFP_ATOMIC,
 715                                   "%s%s", BATADV_UEV_ACTION_VAR,
 716                                   batadv_uev_action_str[action]);
 717         if (!uevent_env[1])
 718                 goto out;
 719 
 720         /* If the event is DEL, ignore the data field */
 721         if (action != BATADV_UEV_DEL) {
 722                 uevent_env[2] = kasprintf(GFP_ATOMIC,
 723                                           "%s%s", BATADV_UEV_DATA_VAR, data);
 724                 if (!uevent_env[2])
 725                         goto out;
 726         }
 727 
 728         ret = kobject_uevent_env(bat_kobj, KOBJ_CHANGE, uevent_env);
 729 out:
 730         kfree(uevent_env[0]);
 731         kfree(uevent_env[1]);
 732         kfree(uevent_env[2]);
 733 
 734         if (ret)
 735                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 736                            "Impossible to send uevent for (%s,%s,%s) event (err: %d)\n",
 737                            batadv_uev_type_str[type],
 738                            batadv_uev_action_str[action],
 739                            (action == BATADV_UEV_DEL ? "NULL" : data), ret);
 740         return ret;
 741 }
 742 
 743 module_init(batadv_init);
 744 module_exit(batadv_exit);
 745 
 746 MODULE_LICENSE("GPL");
 747 
 748 MODULE_AUTHOR(BATADV_DRIVER_AUTHOR);
 749 MODULE_DESCRIPTION(BATADV_DRIVER_DESC);
 750 MODULE_SUPPORTED_DEVICE(BATADV_DRIVER_DEVICE);
 751 MODULE_VERSION(BATADV_SOURCE_VERSION);
 752 MODULE_ALIAS_RTNL_LINK("batadv");
 753 MODULE_ALIAS_GENL_FAMILY(BATADV_NL_NAME);
/* [<][>][^][v][top][bottom][index][help] */
root/net/batman-adv/main.c

DEFINITIONS
