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   1/* Copyright (C) 2007-2014 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 <linux/crc32c.h>
  19#include <linux/highmem.h>
  20#include <linux/if_vlan.h>
  21#include <net/ip.h>
  22#include <net/ipv6.h>
  23#include <net/dsfield.h>
  24#include "main.h"
  25#include "sysfs.h"
  26#include "debugfs.h"
  27#include "routing.h"
  28#include "send.h"
  29#include "originator.h"
  30#include "soft-interface.h"
  31#include "icmp_socket.h"
  32#include "translation-table.h"
  33#include "hard-interface.h"
  34#include "gateway_client.h"
  35#include "bridge_loop_avoidance.h"
  36#include "distributed-arp-table.h"
  37#include "multicast.h"
  38#include "gateway_common.h"
  39#include "hash.h"
  40#include "bat_algo.h"
  41#include "network-coding.h"
  42#include "fragmentation.h"
  43
  44
  45/* List manipulations on hardif_list have to be rtnl_lock()'ed,
  46 * list traversals just rcu-locked
  47 */
  48struct list_head batadv_hardif_list;
  49static int (*batadv_rx_handler[256])(struct sk_buff *,
  50				     struct batadv_hard_iface *);
  51char batadv_routing_algo[20] = "BATMAN_IV";
  52static struct hlist_head batadv_algo_list;
  53
  54unsigned char batadv_broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
  55
  56struct workqueue_struct *batadv_event_workqueue;
  57
  58static void batadv_recv_handler_init(void);
  59
  60static int __init batadv_init(void)
  61{
  62	INIT_LIST_HEAD(&batadv_hardif_list);
  63	INIT_HLIST_HEAD(&batadv_algo_list);
  64
  65	batadv_recv_handler_init();
  66
  67	batadv_iv_init();
  68	batadv_nc_init();
  69
  70	batadv_event_workqueue = create_singlethread_workqueue("bat_events");
  71
  72	if (!batadv_event_workqueue)
  73		return -ENOMEM;
  74
  75	batadv_socket_init();
  76	batadv_debugfs_init();
  77
  78	register_netdevice_notifier(&batadv_hard_if_notifier);
  79	rtnl_link_register(&batadv_link_ops);
  80
  81	pr_info("B.A.T.M.A.N. advanced %s (compatibility version %i) loaded\n",
  82		BATADV_SOURCE_VERSION, BATADV_COMPAT_VERSION);
  83
  84	return 0;
  85}
  86
  87static void __exit batadv_exit(void)
  88{
  89	batadv_debugfs_destroy();
  90	rtnl_link_unregister(&batadv_link_ops);
  91	unregister_netdevice_notifier(&batadv_hard_if_notifier);
  92	batadv_hardif_remove_interfaces();
  93
  94	flush_workqueue(batadv_event_workqueue);
  95	destroy_workqueue(batadv_event_workqueue);
  96	batadv_event_workqueue = NULL;
  97
  98	rcu_barrier();
  99}
 100
 101int batadv_mesh_init(struct net_device *soft_iface)
 102{
 103	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 104	int ret;
 105
 106	spin_lock_init(&bat_priv->forw_bat_list_lock);
 107	spin_lock_init(&bat_priv->forw_bcast_list_lock);
 108	spin_lock_init(&bat_priv->tt.changes_list_lock);
 109	spin_lock_init(&bat_priv->tt.req_list_lock);
 110	spin_lock_init(&bat_priv->tt.roam_list_lock);
 111	spin_lock_init(&bat_priv->tt.last_changeset_lock);
 112	spin_lock_init(&bat_priv->tt.commit_lock);
 113	spin_lock_init(&bat_priv->gw.list_lock);
 114#ifdef CONFIG_BATMAN_ADV_MCAST
 115	spin_lock_init(&bat_priv->mcast.want_lists_lock);
 116#endif
 117	spin_lock_init(&bat_priv->tvlv.container_list_lock);
 118	spin_lock_init(&bat_priv->tvlv.handler_list_lock);
 119	spin_lock_init(&bat_priv->softif_vlan_list_lock);
 120
 121	INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
 122	INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
 123	INIT_HLIST_HEAD(&bat_priv->gw.list);
 124#ifdef CONFIG_BATMAN_ADV_MCAST
 125	INIT_HLIST_HEAD(&bat_priv->mcast.want_all_unsnoopables_list);
 126	INIT_HLIST_HEAD(&bat_priv->mcast.want_all_ipv4_list);
 127	INIT_HLIST_HEAD(&bat_priv->mcast.want_all_ipv6_list);
 128#endif
 129	INIT_LIST_HEAD(&bat_priv->tt.changes_list);
 130	INIT_LIST_HEAD(&bat_priv->tt.req_list);
 131	INIT_LIST_HEAD(&bat_priv->tt.roam_list);
 132#ifdef CONFIG_BATMAN_ADV_MCAST
 133	INIT_HLIST_HEAD(&bat_priv->mcast.mla_list);
 134#endif
 135	INIT_HLIST_HEAD(&bat_priv->tvlv.container_list);
 136	INIT_HLIST_HEAD(&bat_priv->tvlv.handler_list);
 137	INIT_HLIST_HEAD(&bat_priv->softif_vlan_list);
 138
 139	ret = batadv_originator_init(bat_priv);
 140	if (ret < 0)
 141		goto err;
 142
 143	ret = batadv_tt_init(bat_priv);
 144	if (ret < 0)
 145		goto err;
 146
 147	ret = batadv_bla_init(bat_priv);
 148	if (ret < 0)
 149		goto err;
 150
 151	ret = batadv_dat_init(bat_priv);
 152	if (ret < 0)
 153		goto err;
 154
 155	ret = batadv_nc_mesh_init(bat_priv);
 156	if (ret < 0)
 157		goto err;
 158
 159	batadv_gw_init(bat_priv);
 160	batadv_mcast_init(bat_priv);
 161
 162	atomic_set(&bat_priv->gw.reselect, 0);
 163	atomic_set(&bat_priv->mesh_state, BATADV_MESH_ACTIVE);
 164
 165	return 0;
 166
 167err:
 168	batadv_mesh_free(soft_iface);
 169	return ret;
 170}
 171
 172void batadv_mesh_free(struct net_device *soft_iface)
 173{
 174	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 175
 176	atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);
 177
 178	batadv_purge_outstanding_packets(bat_priv, NULL);
 179
 180	batadv_gw_node_purge(bat_priv);
 181	batadv_nc_mesh_free(bat_priv);
 182	batadv_dat_free(bat_priv);
 183	batadv_bla_free(bat_priv);
 184
 185	batadv_mcast_free(bat_priv);
 186
 187	/* Free the TT and the originator tables only after having terminated
 188	 * all the other depending components which may use these structures for
 189	 * their purposes.
 190	 */
 191	batadv_tt_free(bat_priv);
 192
 193	/* Since the originator table clean up routine is accessing the TT
 194	 * tables as well, it has to be invoked after the TT tables have been
 195	 * freed and marked as empty. This ensures that no cleanup RCU callbacks
 196	 * accessing the TT data are scheduled for later execution.
 197	 */
 198	batadv_originator_free(bat_priv);
 199
 200	batadv_gw_free(bat_priv);
 201
 202	free_percpu(bat_priv->bat_counters);
 203	bat_priv->bat_counters = NULL;
 204
 205	atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
 206}
 207
 208/**
 209 * batadv_is_my_mac - check if the given mac address belongs to any of the real
 210 * interfaces in the current mesh
 211 * @bat_priv: the bat priv with all the soft interface information
 212 * @addr: the address to check
 213 */
 214int batadv_is_my_mac(struct batadv_priv *bat_priv, const uint8_t *addr)
 215{
 216	const struct batadv_hard_iface *hard_iface;
 217
 218	rcu_read_lock();
 219	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 220		if (hard_iface->if_status != BATADV_IF_ACTIVE)
 221			continue;
 222
 223		if (hard_iface->soft_iface != bat_priv->soft_iface)
 224			continue;
 225
 226		if (batadv_compare_eth(hard_iface->net_dev->dev_addr, addr)) {
 227			rcu_read_unlock();
 228			return 1;
 229		}
 230	}
 231	rcu_read_unlock();
 232	return 0;
 233}
 234
 235/**
 236 * batadv_seq_print_text_primary_if_get - called from debugfs table printing
 237 *  function that requires the primary interface
 238 * @seq: debugfs table seq_file struct
 239 *
 240 * Returns primary interface if found or NULL otherwise.
 241 */
 242struct batadv_hard_iface *
 243batadv_seq_print_text_primary_if_get(struct seq_file *seq)
 244{
 245	struct net_device *net_dev = (struct net_device *)seq->private;
 246	struct batadv_priv *bat_priv = netdev_priv(net_dev);
 247	struct batadv_hard_iface *primary_if;
 248
 249	primary_if = batadv_primary_if_get_selected(bat_priv);
 250
 251	if (!primary_if) {
 252		seq_printf(seq,
 253			   "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
 254			   net_dev->name);
 255		goto out;
 256	}
 257
 258	if (primary_if->if_status == BATADV_IF_ACTIVE)
 259		goto out;
 260
 261	seq_printf(seq,
 262		   "BATMAN mesh %s disabled - primary interface not active\n",
 263		   net_dev->name);
 264	batadv_hardif_free_ref(primary_if);
 265	primary_if = NULL;
 266
 267out:
 268	return primary_if;
 269}
 270
 271/**
 272 * batadv_max_header_len - calculate maximum encapsulation overhead for a
 273 *  payload packet
 274 *
 275 * Return the maximum encapsulation overhead in bytes.
 276 */
 277int batadv_max_header_len(void)
 278{
 279	int header_len = 0;
 280
 281	header_len = max_t(int, header_len,
 282			   sizeof(struct batadv_unicast_packet));
 283	header_len = max_t(int, header_len,
 284			   sizeof(struct batadv_unicast_4addr_packet));
 285	header_len = max_t(int, header_len,
 286			   sizeof(struct batadv_bcast_packet));
 287
 288#ifdef CONFIG_BATMAN_ADV_NC
 289	header_len = max_t(int, header_len,
 290			   sizeof(struct batadv_coded_packet));
 291#endif
 292
 293	return header_len + ETH_HLEN;
 294}
 295
 296/**
 297 * batadv_skb_set_priority - sets skb priority according to packet content
 298 * @skb: the packet to be sent
 299 * @offset: offset to the packet content
 300 *
 301 * This function sets a value between 256 and 263 (802.1d priority), which
 302 * can be interpreted by the cfg80211 or other drivers.
 303 */
 304void batadv_skb_set_priority(struct sk_buff *skb, int offset)
 305{
 306	struct iphdr ip_hdr_tmp, *ip_hdr;
 307	struct ipv6hdr ip6_hdr_tmp, *ip6_hdr;
 308	struct ethhdr ethhdr_tmp, *ethhdr;
 309	struct vlan_ethhdr *vhdr, vhdr_tmp;
 310	u32 prio;
 311
 312	/* already set, do nothing */
 313	if (skb->priority >= 256 && skb->priority <= 263)
 314		return;
 315
 316	ethhdr = skb_header_pointer(skb, offset, sizeof(*ethhdr), &ethhdr_tmp);
 317	if (!ethhdr)
 318		return;
 319
 320	switch (ethhdr->h_proto) {
 321	case htons(ETH_P_8021Q):
 322		vhdr = skb_header_pointer(skb, offset + sizeof(*vhdr),
 323					  sizeof(*vhdr), &vhdr_tmp);
 324		if (!vhdr)
 325			return;
 326		prio = ntohs(vhdr->h_vlan_TCI) & VLAN_PRIO_MASK;
 327		prio = prio >> VLAN_PRIO_SHIFT;
 328		break;
 329	case htons(ETH_P_IP):
 330		ip_hdr = skb_header_pointer(skb, offset + sizeof(*ethhdr),
 331					    sizeof(*ip_hdr), &ip_hdr_tmp);
 332		if (!ip_hdr)
 333			return;
 334		prio = (ipv4_get_dsfield(ip_hdr) & 0xfc) >> 5;
 335		break;
 336	case htons(ETH_P_IPV6):
 337		ip6_hdr = skb_header_pointer(skb, offset + sizeof(*ethhdr),
 338					     sizeof(*ip6_hdr), &ip6_hdr_tmp);
 339		if (!ip6_hdr)
 340			return;
 341		prio = (ipv6_get_dsfield(ip6_hdr) & 0xfc) >> 5;
 342		break;
 343	default:
 344		return;
 345	}
 346
 347	skb->priority = prio + 256;
 348}
 349
 350static int batadv_recv_unhandled_packet(struct sk_buff *skb,
 351					struct batadv_hard_iface *recv_if)
 352{
 353	return NET_RX_DROP;
 354}
 355
 356/* incoming packets with the batman ethertype received on any active hard
 357 * interface
 358 */
 359int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
 360			   struct packet_type *ptype,
 361			   struct net_device *orig_dev)
 362{
 363	struct batadv_priv *bat_priv;
 364	struct batadv_ogm_packet *batadv_ogm_packet;
 365	struct batadv_hard_iface *hard_iface;
 366	uint8_t idx;
 367	int ret;
 368
 369	hard_iface = container_of(ptype, struct batadv_hard_iface,
 370				  batman_adv_ptype);
 371	skb = skb_share_check(skb, GFP_ATOMIC);
 372
 373	/* skb was released by skb_share_check() */
 374	if (!skb)
 375		goto err_out;
 376
 377	/* packet should hold at least type and version */
 378	if (unlikely(!pskb_may_pull(skb, 2)))
 379		goto err_free;
 380
 381	/* expect a valid ethernet header here. */
 382	if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb)))
 383		goto err_free;
 384
 385	if (!hard_iface->soft_iface)
 386		goto err_free;
 387
 388	bat_priv = netdev_priv(hard_iface->soft_iface);
 389
 390	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
 391		goto err_free;
 392
 393	/* discard frames on not active interfaces */
 394	if (hard_iface->if_status != BATADV_IF_ACTIVE)
 395		goto err_free;
 396
 397	batadv_ogm_packet = (struct batadv_ogm_packet *)skb->data;
 398
 399	if (batadv_ogm_packet->version != BATADV_COMPAT_VERSION) {
 400		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 401			   "Drop packet: incompatible batman version (%i)\n",
 402			   batadv_ogm_packet->version);
 403		goto err_free;
 404	}
 405
 406	/* all receive handlers return whether they received or reused
 407	 * the supplied skb. if not, we have to free the skb.
 408	 */
 409	idx = batadv_ogm_packet->packet_type;
 410	ret = (*batadv_rx_handler[idx])(skb, hard_iface);
 411
 412	if (ret == NET_RX_DROP)
 413		kfree_skb(skb);
 414
 415	/* return NET_RX_SUCCESS in any case as we
 416	 * most probably dropped the packet for
 417	 * routing-logical reasons.
 418	 */
 419	return NET_RX_SUCCESS;
 420
 421err_free:
 422	kfree_skb(skb);
 423err_out:
 424	return NET_RX_DROP;
 425}
 426
 427static void batadv_recv_handler_init(void)
 428{
 429	int i;
 430
 431	for (i = 0; i < ARRAY_SIZE(batadv_rx_handler); i++)
 432		batadv_rx_handler[i] = batadv_recv_unhandled_packet;
 433
 434	for (i = BATADV_UNICAST_MIN; i <= BATADV_UNICAST_MAX; i++)
 435		batadv_rx_handler[i] = batadv_recv_unhandled_unicast_packet;
 436
 437	/* compile time checks for sizes */
 438	BUILD_BUG_ON(sizeof(struct batadv_bla_claim_dst) != 6);
 439	BUILD_BUG_ON(sizeof(struct batadv_ogm_packet) != 24);
 440	BUILD_BUG_ON(sizeof(struct batadv_icmp_header) != 20);
 441	BUILD_BUG_ON(sizeof(struct batadv_icmp_packet) != 20);
 442	BUILD_BUG_ON(sizeof(struct batadv_icmp_packet_rr) != 116);
 443	BUILD_BUG_ON(sizeof(struct batadv_unicast_packet) != 10);
 444	BUILD_BUG_ON(sizeof(struct batadv_unicast_4addr_packet) != 18);
 445	BUILD_BUG_ON(sizeof(struct batadv_frag_packet) != 20);
 446	BUILD_BUG_ON(sizeof(struct batadv_bcast_packet) != 14);
 447	BUILD_BUG_ON(sizeof(struct batadv_coded_packet) != 46);
 448	BUILD_BUG_ON(sizeof(struct batadv_unicast_tvlv_packet) != 20);
 449	BUILD_BUG_ON(sizeof(struct batadv_tvlv_hdr) != 4);
 450	BUILD_BUG_ON(sizeof(struct batadv_tvlv_gateway_data) != 8);
 451	BUILD_BUG_ON(sizeof(struct batadv_tvlv_tt_vlan_data) != 8);
 452	BUILD_BUG_ON(sizeof(struct batadv_tvlv_tt_change) != 12);
 453	BUILD_BUG_ON(sizeof(struct batadv_tvlv_roam_adv) != 8);
 454
 455	/* broadcast packet */
 456	batadv_rx_handler[BATADV_BCAST] = batadv_recv_bcast_packet;
 457
 458	/* unicast packets ... */
 459	/* unicast with 4 addresses packet */
 460	batadv_rx_handler[BATADV_UNICAST_4ADDR] = batadv_recv_unicast_packet;
 461	/* unicast packet */
 462	batadv_rx_handler[BATADV_UNICAST] = batadv_recv_unicast_packet;
 463	/* unicast tvlv packet */
 464	batadv_rx_handler[BATADV_UNICAST_TVLV] = batadv_recv_unicast_tvlv;
 465	/* batman icmp packet */
 466	batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet;
 467	/* Fragmented packets */
 468	batadv_rx_handler[BATADV_UNICAST_FRAG] = batadv_recv_frag_packet;
 469}
 470
 471int
 472batadv_recv_handler_register(uint8_t packet_type,
 473			     int (*recv_handler)(struct sk_buff *,
 474						 struct batadv_hard_iface *))
 475{
 476	int (*curr)(struct sk_buff *,
 477		    struct batadv_hard_iface *);
 478	curr = batadv_rx_handler[packet_type];
 479
 480	if ((curr != batadv_recv_unhandled_packet) &&
 481	    (curr != batadv_recv_unhandled_unicast_packet))
 482		return -EBUSY;
 483
 484	batadv_rx_handler[packet_type] = recv_handler;
 485	return 0;
 486}
 487
 488void batadv_recv_handler_unregister(uint8_t packet_type)
 489{
 490	batadv_rx_handler[packet_type] = batadv_recv_unhandled_packet;
 491}
 492
 493static struct batadv_algo_ops *batadv_algo_get(char *name)
 494{
 495	struct batadv_algo_ops *bat_algo_ops = NULL, *bat_algo_ops_tmp;
 496
 497	hlist_for_each_entry(bat_algo_ops_tmp, &batadv_algo_list, list) {
 498		if (strcmp(bat_algo_ops_tmp->name, name) != 0)
 499			continue;
 500
 501		bat_algo_ops = bat_algo_ops_tmp;
 502		break;
 503	}
 504
 505	return bat_algo_ops;
 506}
 507
 508int batadv_algo_register(struct batadv_algo_ops *bat_algo_ops)
 509{
 510	struct batadv_algo_ops *bat_algo_ops_tmp;
 511	int ret;
 512
 513	bat_algo_ops_tmp = batadv_algo_get(bat_algo_ops->name);
 514	if (bat_algo_ops_tmp) {
 515		pr_info("Trying to register already registered routing algorithm: %s\n",
 516			bat_algo_ops->name);
 517		ret = -EEXIST;
 518		goto out;
 519	}
 520
 521	/* all algorithms must implement all ops (for now) */
 522	if (!bat_algo_ops->bat_iface_enable ||
 523	    !bat_algo_ops->bat_iface_disable ||
 524	    !bat_algo_ops->bat_iface_update_mac ||
 525	    !bat_algo_ops->bat_primary_iface_set ||
 526	    !bat_algo_ops->bat_ogm_schedule ||
 527	    !bat_algo_ops->bat_ogm_emit ||
 528	    !bat_algo_ops->bat_neigh_cmp ||
 529	    !bat_algo_ops->bat_neigh_is_equiv_or_better) {
 530		pr_info("Routing algo '%s' does not implement required ops\n",
 531			bat_algo_ops->name);
 532		ret = -EINVAL;
 533		goto out;
 534	}
 535
 536	INIT_HLIST_NODE(&bat_algo_ops->list);
 537	hlist_add_head(&bat_algo_ops->list, &batadv_algo_list);
 538	ret = 0;
 539
 540out:
 541	return ret;
 542}
 543
 544int batadv_algo_select(struct batadv_priv *bat_priv, char *name)
 545{
 546	struct batadv_algo_ops *bat_algo_ops;
 547	int ret = -EINVAL;
 548
 549	bat_algo_ops = batadv_algo_get(name);
 550	if (!bat_algo_ops)
 551		goto out;
 552
 553	bat_priv->bat_algo_ops = bat_algo_ops;
 554	ret = 0;
 555
 556out:
 557	return ret;
 558}
 559
 560int batadv_algo_seq_print_text(struct seq_file *seq, void *offset)
 561{
 562	struct batadv_algo_ops *bat_algo_ops;
 563
 564	seq_puts(seq, "Available routing algorithms:\n");
 565
 566	hlist_for_each_entry(bat_algo_ops, &batadv_algo_list, list) {
 567		seq_printf(seq, "%s\n", bat_algo_ops->name);
 568	}
 569
 570	return 0;
 571}
 572
 573/**
 574 * batadv_skb_crc32 - calculate CRC32 of the whole packet and skip bytes in
 575 *  the header
 576 * @skb: skb pointing to fragmented socket buffers
 577 * @payload_ptr: Pointer to position inside the head buffer of the skb
 578 *  marking the start of the data to be CRC'ed
 579 *
 580 * payload_ptr must always point to an address in the skb head buffer and not to
 581 * a fragment.
 582 */
 583__be32 batadv_skb_crc32(struct sk_buff *skb, u8 *payload_ptr)
 584{
 585	u32 crc = 0;
 586	unsigned int from;
 587	unsigned int to = skb->len;
 588	struct skb_seq_state st;
 589	const u8 *data;
 590	unsigned int len;
 591	unsigned int consumed = 0;
 592
 593	from = (unsigned int)(payload_ptr - skb->data);
 594
 595	skb_prepare_seq_read(skb, from, to, &st);
 596	while ((len = skb_seq_read(consumed, &data, &st)) != 0) {
 597		crc = crc32c(crc, data, len);
 598		consumed += len;
 599	}
 600
 601	return htonl(crc);
 602}
 603
 604/**
 605 * batadv_tvlv_handler_free_ref - decrement the tvlv handler refcounter and
 606 *  possibly free it
 607 * @tvlv_handler: the tvlv handler to free
 608 */
 609static void
 610batadv_tvlv_handler_free_ref(struct batadv_tvlv_handler *tvlv_handler)
 611{
 612	if (atomic_dec_and_test(&tvlv_handler->refcount))
 613		kfree_rcu(tvlv_handler, rcu);
 614}
 615
 616/**
 617 * batadv_tvlv_handler_get - retrieve tvlv handler from the tvlv handler list
 618 *  based on the provided type and version (both need to match)
 619 * @bat_priv: the bat priv with all the soft interface information
 620 * @type: tvlv handler type to look for
 621 * @version: tvlv handler version to look for
 622 *
 623 * Returns tvlv handler if found or NULL otherwise.
 624 */
 625static struct batadv_tvlv_handler
 626*batadv_tvlv_handler_get(struct batadv_priv *bat_priv,
 627			 uint8_t type, uint8_t version)
 628{
 629	struct batadv_tvlv_handler *tvlv_handler_tmp, *tvlv_handler = NULL;
 630
 631	rcu_read_lock();
 632	hlist_for_each_entry_rcu(tvlv_handler_tmp,
 633				 &bat_priv->tvlv.handler_list, list) {
 634		if (tvlv_handler_tmp->type != type)
 635			continue;
 636
 637		if (tvlv_handler_tmp->version != version)
 638			continue;
 639
 640		if (!atomic_inc_not_zero(&tvlv_handler_tmp->refcount))
 641			continue;
 642
 643		tvlv_handler = tvlv_handler_tmp;
 644		break;
 645	}
 646	rcu_read_unlock();
 647
 648	return tvlv_handler;
 649}
 650
 651/**
 652 * batadv_tvlv_container_free_ref - decrement the tvlv container refcounter and
 653 *  possibly free it
 654 * @tvlv_handler: the tvlv container to free
 655 */
 656static void batadv_tvlv_container_free_ref(struct batadv_tvlv_container *tvlv)
 657{
 658	if (atomic_dec_and_test(&tvlv->refcount))
 659		kfree(tvlv);
 660}
 661
 662/**
 663 * batadv_tvlv_container_get - retrieve tvlv container from the tvlv container
 664 *  list based on the provided type and version (both need to match)
 665 * @bat_priv: the bat priv with all the soft interface information
 666 * @type: tvlv container type to look for
 667 * @version: tvlv container version to look for
 668 *
 669 * Has to be called with the appropriate locks being acquired
 670 * (tvlv.container_list_lock).
 671 *
 672 * Returns tvlv container if found or NULL otherwise.
 673 */
 674static struct batadv_tvlv_container
 675*batadv_tvlv_container_get(struct batadv_priv *bat_priv,
 676			   uint8_t type, uint8_t version)
 677{
 678	struct batadv_tvlv_container *tvlv_tmp, *tvlv = NULL;
 679
 680	hlist_for_each_entry(tvlv_tmp, &bat_priv->tvlv.container_list, list) {
 681		if (tvlv_tmp->tvlv_hdr.type != type)
 682			continue;
 683
 684		if (tvlv_tmp->tvlv_hdr.version != version)
 685			continue;
 686
 687		if (!atomic_inc_not_zero(&tvlv_tmp->refcount))
 688			continue;
 689
 690		tvlv = tvlv_tmp;
 691		break;
 692	}
 693
 694	return tvlv;
 695}
 696
 697/**
 698 * batadv_tvlv_container_list_size - calculate the size of the tvlv container
 699 *  list entries
 700 * @bat_priv: the bat priv with all the soft interface information
 701 *
 702 * Has to be called with the appropriate locks being acquired
 703 * (tvlv.container_list_lock).
 704 *
 705 * Returns size of all currently registered tvlv containers in bytes.
 706 */
 707static uint16_t batadv_tvlv_container_list_size(struct batadv_priv *bat_priv)
 708{
 709	struct batadv_tvlv_container *tvlv;
 710	uint16_t tvlv_len = 0;
 711
 712	hlist_for_each_entry(tvlv, &bat_priv->tvlv.container_list, list) {
 713		tvlv_len += sizeof(struct batadv_tvlv_hdr);
 714		tvlv_len += ntohs(tvlv->tvlv_hdr.len);
 715	}
 716
 717	return tvlv_len;
 718}
 719
 720/**
 721 * batadv_tvlv_container_remove - remove tvlv container from the tvlv container
 722 *  list
 723 * @tvlv: the to be removed tvlv container
 724 *
 725 * Has to be called with the appropriate locks being acquired
 726 * (tvlv.container_list_lock).
 727 */
 728static void batadv_tvlv_container_remove(struct batadv_tvlv_container *tvlv)
 729{
 730	if (!tvlv)
 731		return;
 732
 733	hlist_del(&tvlv->list);
 734
 735	/* first call to decrement the counter, second call to free */
 736	batadv_tvlv_container_free_ref(tvlv);
 737	batadv_tvlv_container_free_ref(tvlv);
 738}
 739
 740/**
 741 * batadv_tvlv_container_unregister - unregister tvlv container based on the
 742 *  provided type and version (both need to match)
 743 * @bat_priv: the bat priv with all the soft interface information
 744 * @type: tvlv container type to unregister
 745 * @version: tvlv container type to unregister
 746 */
 747void batadv_tvlv_container_unregister(struct batadv_priv *bat_priv,
 748				      uint8_t type, uint8_t version)
 749{
 750	struct batadv_tvlv_container *tvlv;
 751
 752	spin_lock_bh(&bat_priv->tvlv.container_list_lock);
 753	tvlv = batadv_tvlv_container_get(bat_priv, type, version);
 754	batadv_tvlv_container_remove(tvlv);
 755	spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
 756}
 757
 758/**
 759 * batadv_tvlv_container_register - register tvlv type, version and content
 760 *  to be propagated with each (primary interface) OGM
 761 * @bat_priv: the bat priv with all the soft interface information
 762 * @type: tvlv container type
 763 * @version: tvlv container version
 764 * @tvlv_value: tvlv container content
 765 * @tvlv_value_len: tvlv container content length
 766 *
 767 * If a container of the same type and version was already registered the new
 768 * content is going to replace the old one.
 769 */
 770void batadv_tvlv_container_register(struct batadv_priv *bat_priv,
 771				    uint8_t type, uint8_t version,
 772				    void *tvlv_value, uint16_t tvlv_value_len)
 773{
 774	struct batadv_tvlv_container *tvlv_old, *tvlv_new;
 775
 776	if (!tvlv_value)
 777		tvlv_value_len = 0;
 778
 779	tvlv_new = kzalloc(sizeof(*tvlv_new) + tvlv_value_len, GFP_ATOMIC);
 780	if (!tvlv_new)
 781		return;
 782
 783	tvlv_new->tvlv_hdr.version = version;
 784	tvlv_new->tvlv_hdr.type = type;
 785	tvlv_new->tvlv_hdr.len = htons(tvlv_value_len);
 786
 787	memcpy(tvlv_new + 1, tvlv_value, ntohs(tvlv_new->tvlv_hdr.len));
 788	INIT_HLIST_NODE(&tvlv_new->list);
 789	atomic_set(&tvlv_new->refcount, 1);
 790
 791	spin_lock_bh(&bat_priv->tvlv.container_list_lock);
 792	tvlv_old = batadv_tvlv_container_get(bat_priv, type, version);
 793	batadv_tvlv_container_remove(tvlv_old);
 794	hlist_add_head(&tvlv_new->list, &bat_priv->tvlv.container_list);
 795	spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
 796}
 797
 798/**
 799 * batadv_tvlv_realloc_packet_buff - reallocate packet buffer to accomodate
 800 *  requested packet size
 801 * @packet_buff: packet buffer
 802 * @packet_buff_len: packet buffer size
 803 * @packet_min_len: requested packet minimum size
 804 * @additional_packet_len: requested additional packet size on top of minimum
 805 *  size
 806 *
 807 * Returns true of the packet buffer could be changed to the requested size,
 808 * false otherwise.
 809 */
 810static bool batadv_tvlv_realloc_packet_buff(unsigned char **packet_buff,
 811					    int *packet_buff_len,
 812					    int min_packet_len,
 813					    int additional_packet_len)
 814{
 815	unsigned char *new_buff;
 816
 817	new_buff = kmalloc(min_packet_len + additional_packet_len, GFP_ATOMIC);
 818
 819	/* keep old buffer if kmalloc should fail */
 820	if (new_buff) {
 821		memcpy(new_buff, *packet_buff, min_packet_len);
 822		kfree(*packet_buff);
 823		*packet_buff = new_buff;
 824		*packet_buff_len = min_packet_len + additional_packet_len;
 825		return true;
 826	}
 827
 828	return false;
 829}
 830
 831/**
 832 * batadv_tvlv_container_ogm_append - append tvlv container content to given
 833 *  OGM packet buffer
 834 * @bat_priv: the bat priv with all the soft interface information
 835 * @packet_buff: ogm packet buffer
 836 * @packet_buff_len: ogm packet buffer size including ogm header and tvlv
 837 *  content
 838 * @packet_min_len: ogm header size to be preserved for the OGM itself
 839 *
 840 * The ogm packet might be enlarged or shrunk depending on the current size
 841 * and the size of the to-be-appended tvlv containers.
 842 *
 843 * Returns size of all appended tvlv containers in bytes.
 844 */
 845uint16_t batadv_tvlv_container_ogm_append(struct batadv_priv *bat_priv,
 846					  unsigned char **packet_buff,
 847					  int *packet_buff_len,
 848					  int packet_min_len)
 849{
 850	struct batadv_tvlv_container *tvlv;
 851	struct batadv_tvlv_hdr *tvlv_hdr;
 852	uint16_t tvlv_value_len;
 853	void *tvlv_value;
 854	bool ret;
 855
 856	spin_lock_bh(&bat_priv->tvlv.container_list_lock);
 857	tvlv_value_len = batadv_tvlv_container_list_size(bat_priv);
 858
 859	ret = batadv_tvlv_realloc_packet_buff(packet_buff, packet_buff_len,
 860					      packet_min_len, tvlv_value_len);
 861
 862	if (!ret)
 863		goto end;
 864
 865	if (!tvlv_value_len)
 866		goto end;
 867
 868	tvlv_value = (*packet_buff) + packet_min_len;
 869
 870	hlist_for_each_entry(tvlv, &bat_priv->tvlv.container_list, list) {
 871		tvlv_hdr = tvlv_value;
 872		tvlv_hdr->type = tvlv->tvlv_hdr.type;
 873		tvlv_hdr->version = tvlv->tvlv_hdr.version;
 874		tvlv_hdr->len = tvlv->tvlv_hdr.len;
 875		tvlv_value = tvlv_hdr + 1;
 876		memcpy(tvlv_value, tvlv + 1, ntohs(tvlv->tvlv_hdr.len));
 877		tvlv_value = (uint8_t *)tvlv_value + ntohs(tvlv->tvlv_hdr.len);
 878	}
 879
 880end:
 881	spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
 882	return tvlv_value_len;
 883}
 884
 885/**
 886 * batadv_tvlv_call_handler - parse the given tvlv buffer to call the
 887 *  appropriate handlers
 888 * @bat_priv: the bat priv with all the soft interface information
 889 * @tvlv_handler: tvlv callback function handling the tvlv content
 890 * @ogm_source: flag indicating wether the tvlv is an ogm or a unicast packet
 891 * @orig_node: orig node emitting the ogm packet
 892 * @src: source mac address of the unicast packet
 893 * @dst: destination mac address of the unicast packet
 894 * @tvlv_value: tvlv content
 895 * @tvlv_value_len: tvlv content length
 896 *
 897 * Returns success if handler was not found or the return value of the handler
 898 * callback.
 899 */
 900static int batadv_tvlv_call_handler(struct batadv_priv *bat_priv,
 901				    struct batadv_tvlv_handler *tvlv_handler,
 902				    bool ogm_source,
 903				    struct batadv_orig_node *orig_node,
 904				    uint8_t *src, uint8_t *dst,
 905				    void *tvlv_value, uint16_t tvlv_value_len)
 906{
 907	if (!tvlv_handler)
 908		return NET_RX_SUCCESS;
 909
 910	if (ogm_source) {
 911		if (!tvlv_handler->ogm_handler)
 912			return NET_RX_SUCCESS;
 913
 914		if (!orig_node)
 915			return NET_RX_SUCCESS;
 916
 917		tvlv_handler->ogm_handler(bat_priv, orig_node,
 918					  BATADV_NO_FLAGS,
 919					  tvlv_value, tvlv_value_len);
 920		tvlv_handler->flags |= BATADV_TVLV_HANDLER_OGM_CALLED;
 921	} else {
 922		if (!src)
 923			return NET_RX_SUCCESS;
 924
 925		if (!dst)
 926			return NET_RX_SUCCESS;
 927
 928		if (!tvlv_handler->unicast_handler)
 929			return NET_RX_SUCCESS;
 930
 931		return tvlv_handler->unicast_handler(bat_priv, src,
 932						     dst, tvlv_value,
 933						     tvlv_value_len);
 934	}
 935
 936	return NET_RX_SUCCESS;
 937}
 938
 939/**
 940 * batadv_tvlv_containers_process - parse the given tvlv buffer to call the
 941 *  appropriate handlers
 942 * @bat_priv: the bat priv with all the soft interface information
 943 * @ogm_source: flag indicating wether the tvlv is an ogm or a unicast packet
 944 * @orig_node: orig node emitting the ogm packet
 945 * @src: source mac address of the unicast packet
 946 * @dst: destination mac address of the unicast packet
 947 * @tvlv_value: tvlv content
 948 * @tvlv_value_len: tvlv content length
 949 *
 950 * Returns success when processing an OGM or the return value of all called
 951 * handler callbacks.
 952 */
 953int batadv_tvlv_containers_process(struct batadv_priv *bat_priv,
 954				   bool ogm_source,
 955				   struct batadv_orig_node *orig_node,
 956				   uint8_t *src, uint8_t *dst,
 957				   void *tvlv_value, uint16_t tvlv_value_len)
 958{
 959	struct batadv_tvlv_handler *tvlv_handler;
 960	struct batadv_tvlv_hdr *tvlv_hdr;
 961	uint16_t tvlv_value_cont_len;
 962	uint8_t cifnotfound = BATADV_TVLV_HANDLER_OGM_CIFNOTFND;
 963	int ret = NET_RX_SUCCESS;
 964
 965	while (tvlv_value_len >= sizeof(*tvlv_hdr)) {
 966		tvlv_hdr = tvlv_value;
 967		tvlv_value_cont_len = ntohs(tvlv_hdr->len);
 968		tvlv_value = tvlv_hdr + 1;
 969		tvlv_value_len -= sizeof(*tvlv_hdr);
 970
 971		if (tvlv_value_cont_len > tvlv_value_len)
 972			break;
 973
 974		tvlv_handler = batadv_tvlv_handler_get(bat_priv,
 975						       tvlv_hdr->type,
 976						       tvlv_hdr->version);
 977
 978		ret |= batadv_tvlv_call_handler(bat_priv, tvlv_handler,
 979						ogm_source, orig_node,
 980						src, dst, tvlv_value,
 981						tvlv_value_cont_len);
 982		if (tvlv_handler)
 983			batadv_tvlv_handler_free_ref(tvlv_handler);
 984		tvlv_value = (uint8_t *)tvlv_value + tvlv_value_cont_len;
 985		tvlv_value_len -= tvlv_value_cont_len;
 986	}
 987
 988	if (!ogm_source)
 989		return ret;
 990
 991	rcu_read_lock();
 992	hlist_for_each_entry_rcu(tvlv_handler,
 993				 &bat_priv->tvlv.handler_list, list) {
 994		if ((tvlv_handler->flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND) &&
 995		    !(tvlv_handler->flags & BATADV_TVLV_HANDLER_OGM_CALLED))
 996			tvlv_handler->ogm_handler(bat_priv, orig_node,
 997						  cifnotfound, NULL, 0);
 998
 999		tvlv_handler->flags &= ~BATADV_TVLV_HANDLER_OGM_CALLED;
1000	}
1001	rcu_read_unlock();
1002
1003	return NET_RX_SUCCESS;
1004}
1005
1006/**
1007 * batadv_tvlv_ogm_receive - process an incoming ogm and call the appropriate
1008 *  handlers
1009 * @bat_priv: the bat priv with all the soft interface information
1010 * @batadv_ogm_packet: ogm packet containing the tvlv containers
1011 * @orig_node: orig node emitting the ogm packet
1012 */
1013void batadv_tvlv_ogm_receive(struct batadv_priv *bat_priv,
1014			     struct batadv_ogm_packet *batadv_ogm_packet,
1015			     struct batadv_orig_node *orig_node)
1016{
1017	void *tvlv_value;
1018	uint16_t tvlv_value_len;
1019
1020	if (!batadv_ogm_packet)
1021		return;
1022
1023	tvlv_value_len = ntohs(batadv_ogm_packet->tvlv_len);
1024	if (!tvlv_value_len)
1025		return;
1026
1027	tvlv_value = batadv_ogm_packet + 1;
1028
1029	batadv_tvlv_containers_process(bat_priv, true, orig_node, NULL, NULL,
1030				       tvlv_value, tvlv_value_len);
1031}
1032
1033/**
1034 * batadv_tvlv_handler_register - register tvlv handler based on the provided
1035 *  type and version (both need to match) for ogm tvlv payload and/or unicast
1036 *  payload
1037 * @bat_priv: the bat priv with all the soft interface information
1038 * @optr: ogm tvlv handler callback function. This function receives the orig
1039 *  node, flags and the tvlv content as argument to process.
1040 * @uptr: unicast tvlv handler callback function. This function receives the
1041 *  source & destination of the unicast packet as well as the tvlv content
1042 *  to process.
1043 * @type: tvlv handler type to be registered
1044 * @version: tvlv handler version to be registered
1045 * @flags: flags to enable or disable TVLV API behavior
1046 */
1047void batadv_tvlv_handler_register(struct batadv_priv *bat_priv,
1048				  void (*optr)(struct batadv_priv *bat_priv,
1049					       struct batadv_orig_node *orig,
1050					       uint8_t flags,
1051					       void *tvlv_value,
1052					       uint16_t tvlv_value_len),
1053				  int (*uptr)(struct batadv_priv *bat_priv,
1054					      uint8_t *src, uint8_t *dst,
1055					      void *tvlv_value,
1056					      uint16_t tvlv_value_len),
1057				  uint8_t type, uint8_t version, uint8_t flags)
1058{
1059	struct batadv_tvlv_handler *tvlv_handler;
1060
1061	tvlv_handler = batadv_tvlv_handler_get(bat_priv, type, version);
1062	if (tvlv_handler) {
1063		batadv_tvlv_handler_free_ref(tvlv_handler);
1064		return;
1065	}
1066
1067	tvlv_handler = kzalloc(sizeof(*tvlv_handler), GFP_ATOMIC);
1068	if (!tvlv_handler)
1069		return;
1070
1071	tvlv_handler->ogm_handler = optr;
1072	tvlv_handler->unicast_handler = uptr;
1073	tvlv_handler->type = type;
1074	tvlv_handler->version = version;
1075	tvlv_handler->flags = flags;
1076	atomic_set(&tvlv_handler->refcount, 1);
1077	INIT_HLIST_NODE(&tvlv_handler->list);
1078
1079	spin_lock_bh(&bat_priv->tvlv.handler_list_lock);
1080	hlist_add_head_rcu(&tvlv_handler->list, &bat_priv->tvlv.handler_list);
1081	spin_unlock_bh(&bat_priv->tvlv.handler_list_lock);
1082}
1083
1084/**
1085 * batadv_tvlv_handler_unregister - unregister tvlv handler based on the
1086 *  provided type and version (both need to match)
1087 * @bat_priv: the bat priv with all the soft interface information
1088 * @type: tvlv handler type to be unregistered
1089 * @version: tvlv handler version to be unregistered
1090 */
1091void batadv_tvlv_handler_unregister(struct batadv_priv *bat_priv,
1092				    uint8_t type, uint8_t version)
1093{
1094	struct batadv_tvlv_handler *tvlv_handler;
1095
1096	tvlv_handler = batadv_tvlv_handler_get(bat_priv, type, version);
1097	if (!tvlv_handler)
1098		return;
1099
1100	batadv_tvlv_handler_free_ref(tvlv_handler);
1101	spin_lock_bh(&bat_priv->tvlv.handler_list_lock);
1102	hlist_del_rcu(&tvlv_handler->list);
1103	spin_unlock_bh(&bat_priv->tvlv.handler_list_lock);
1104	batadv_tvlv_handler_free_ref(tvlv_handler);
1105}
1106
1107/**
1108 * batadv_tvlv_unicast_send - send a unicast packet with tvlv payload to the
1109 *  specified host
1110 * @bat_priv: the bat priv with all the soft interface information
1111 * @src: source mac address of the unicast packet
1112 * @dst: destination mac address of the unicast packet
1113 * @type: tvlv type
1114 * @version: tvlv version
1115 * @tvlv_value: tvlv content
1116 * @tvlv_value_len: tvlv content length
1117 */
1118void batadv_tvlv_unicast_send(struct batadv_priv *bat_priv, uint8_t *src,
1119			      uint8_t *dst, uint8_t type, uint8_t version,
1120			      void *tvlv_value, uint16_t tvlv_value_len)
1121{
1122	struct batadv_unicast_tvlv_packet *unicast_tvlv_packet;
1123	struct batadv_tvlv_hdr *tvlv_hdr;
1124	struct batadv_orig_node *orig_node;
1125	struct sk_buff *skb = NULL;
1126	unsigned char *tvlv_buff;
1127	unsigned int tvlv_len;
1128	ssize_t hdr_len = sizeof(*unicast_tvlv_packet);
1129	bool ret = false;
1130
1131	orig_node = batadv_orig_hash_find(bat_priv, dst);
1132	if (!orig_node)
1133		goto out;
1134
1135	tvlv_len = sizeof(*tvlv_hdr) + tvlv_value_len;
1136
1137	skb = netdev_alloc_skb_ip_align(NULL, ETH_HLEN + hdr_len + tvlv_len);
1138	if (!skb)
1139		goto out;
1140
1141	skb->priority = TC_PRIO_CONTROL;
1142	skb_reserve(skb, ETH_HLEN);
1143	tvlv_buff = skb_put(skb, sizeof(*unicast_tvlv_packet) + tvlv_len);
1144	unicast_tvlv_packet = (struct batadv_unicast_tvlv_packet *)tvlv_buff;
1145	unicast_tvlv_packet->packet_type = BATADV_UNICAST_TVLV;
1146	unicast_tvlv_packet->version = BATADV_COMPAT_VERSION;
1147	unicast_tvlv_packet->ttl = BATADV_TTL;
1148	unicast_tvlv_packet->reserved = 0;
1149	unicast_tvlv_packet->tvlv_len = htons(tvlv_len);
1150	unicast_tvlv_packet->align = 0;
1151	ether_addr_copy(unicast_tvlv_packet->src, src);
1152	ether_addr_copy(unicast_tvlv_packet->dst, dst);
1153
1154	tvlv_buff = (unsigned char *)(unicast_tvlv_packet + 1);
1155	tvlv_hdr = (struct batadv_tvlv_hdr *)tvlv_buff;
1156	tvlv_hdr->version = version;
1157	tvlv_hdr->type = type;
1158	tvlv_hdr->len = htons(tvlv_value_len);
1159	tvlv_buff += sizeof(*tvlv_hdr);
1160	memcpy(tvlv_buff, tvlv_value, tvlv_value_len);
1161
1162	if (batadv_send_skb_to_orig(skb, orig_node, NULL) != NET_XMIT_DROP)
1163		ret = true;
1164
1165out:
1166	if (skb && !ret)
1167		kfree_skb(skb);
1168	if (orig_node)
1169		batadv_orig_node_free_ref(orig_node);
1170}
1171
1172/**
1173 * batadv_get_vid - extract the VLAN identifier from skb if any
1174 * @skb: the buffer containing the packet
1175 * @header_len: length of the batman header preceding the ethernet header
1176 *
1177 * If the packet embedded in the skb is vlan tagged this function returns the
1178 * VID with the BATADV_VLAN_HAS_TAG flag. Otherwise BATADV_NO_FLAGS is returned.
1179 */
1180unsigned short batadv_get_vid(struct sk_buff *skb, size_t header_len)
1181{
1182	struct ethhdr *ethhdr = (struct ethhdr *)(skb->data + header_len);
1183	struct vlan_ethhdr *vhdr;
1184	unsigned short vid;
1185
1186	if (ethhdr->h_proto != htons(ETH_P_8021Q))
1187		return BATADV_NO_FLAGS;
1188
1189	if (!pskb_may_pull(skb, header_len + VLAN_ETH_HLEN))
1190		return BATADV_NO_FLAGS;
1191
1192	vhdr = (struct vlan_ethhdr *)(skb->data + header_len);
1193	vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;
1194	vid |= BATADV_VLAN_HAS_TAG;
1195
1196	return vid;
1197}
1198
1199/**
1200 * batadv_vlan_ap_isola_get - return the AP isolation status for the given vlan
1201 * @bat_priv: the bat priv with all the soft interface information
1202 * @vid: the VLAN identifier for which the AP isolation attributed as to be
1203 *  looked up
1204 *
1205 * Returns true if AP isolation is on for the VLAN idenfied by vid, false
1206 * otherwise
1207 */
1208bool batadv_vlan_ap_isola_get(struct batadv_priv *bat_priv, unsigned short vid)
1209{
1210	bool ap_isolation_enabled = false;
1211	struct batadv_softif_vlan *vlan;
1212
1213	/* if the AP isolation is requested on a VLAN, then check for its
1214	 * setting in the proper VLAN private data structure
1215	 */
1216	vlan = batadv_softif_vlan_get(bat_priv, vid);
1217	if (vlan) {
1218		ap_isolation_enabled = atomic_read(&vlan->ap_isolation);
1219		batadv_softif_vlan_free_ref(vlan);
1220	}
1221
1222	return ap_isolation_enabled;
1223}
1224
1225static int batadv_param_set_ra(const char *val, const struct kernel_param *kp)
1226{
1227	struct batadv_algo_ops *bat_algo_ops;
1228	char *algo_name = (char *)val;
1229	size_t name_len = strlen(algo_name);
1230
1231	if (name_len > 0 && algo_name[name_len - 1] == '\n')
1232		algo_name[name_len - 1] = '\0';
1233
1234	bat_algo_ops = batadv_algo_get(algo_name);
1235	if (!bat_algo_ops) {
1236		pr_err("Routing algorithm '%s' is not supported\n", algo_name);
1237		return -EINVAL;
1238	}
1239
1240	return param_set_copystring(algo_name, kp);
1241}
1242
1243static const struct kernel_param_ops batadv_param_ops_ra = {
1244	.set = batadv_param_set_ra,
1245	.get = param_get_string,
1246};
1247
1248static struct kparam_string batadv_param_string_ra = {
1249	.maxlen = sizeof(batadv_routing_algo),
1250	.string = batadv_routing_algo,
1251};
1252
1253module_param_cb(routing_algo, &batadv_param_ops_ra, &batadv_param_string_ra,
1254		0644);
1255module_init(batadv_init);
1256module_exit(batadv_exit);
1257
1258MODULE_LICENSE("GPL");
1259
1260MODULE_AUTHOR(BATADV_DRIVER_AUTHOR);
1261MODULE_DESCRIPTION(BATADV_DRIVER_DESC);
1262MODULE_SUPPORTED_DEVICE(BATADV_DRIVER_DEVICE);
1263MODULE_VERSION(BATADV_SOURCE_VERSION);
  1// SPDX-License-Identifier: GPL-2.0
  2/* Copyright (C) 2007-2020  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 */
 67struct list_head batadv_hardif_list;
 68unsigned int batadv_hardif_generation;
 69static int (*batadv_rx_handler[256])(struct sk_buff *skb,
 70				     struct batadv_hard_iface *recv_if);
 71
 72unsigned char batadv_broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
 73
 74struct workqueue_struct *batadv_event_workqueue;
 75
 76static 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
 82static char *batadv_uev_action_str[] = {
 83	"add",
 84	"del",
 85	"change",
 86	"loopdetect",
 87};
 88
 89static char *batadv_uev_type_str[] = {
 90	"gw",
 91	"bla",
 92};
 93
 94static 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
128err_create_wq:
129	batadv_tt_cache_destroy();
130
131	return -ENOMEM;
132}
133
134static 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 */
157int 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
232err:
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 */
241void 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 */
287bool 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 */
317struct batadv_hard_iface *
318batadv_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
342out:
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 */
353int 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 */
380void 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
426static 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 */
447int 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
515err_free:
516	kfree_skb(skb);
517err_put:
518	batadv_hardif_put(hard_iface);
519err_out:
520	return NET_RX_DROP;
521}
522
523static 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 = sizeof_field(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 */
577int
578batadv_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 */
598void 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 */
644unsigned 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 identified by vid, false
670 * otherwise
671 */
672bool 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 */
699int 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);
729out:
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
743module_init(batadv_init);
744module_exit(batadv_exit);
745
746MODULE_LICENSE("GPL");
747
748MODULE_AUTHOR(BATADV_DRIVER_AUTHOR);
749MODULE_DESCRIPTION(BATADV_DRIVER_DESC);
750MODULE_SUPPORTED_DEVICE(BATADV_DRIVER_DEVICE);
751MODULE_VERSION(BATADV_SOURCE_VERSION);
752MODULE_ALIAS_RTNL_LINK("batadv");
753MODULE_ALIAS_GENL_FAMILY(BATADV_NL_NAME);