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-rw-r--r--net/batman-adv/main.c713
1 files changed, 713 insertions, 0 deletions
diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c
new file mode 100644
index 000000000..bba64b9b3
--- /dev/null
+++ b/net/batman-adv/main.c
@@ -0,0 +1,713 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2007-2018 B.A.T.M.A.N. contributors:
+ *
+ * Marek Lindner, Simon Wunderlich
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "main.h"
+
+#include <linux/atomic.h>
+#include <linux/build_bug.h>
+#include <linux/byteorder/generic.h>
+#include <linux/crc32c.h>
+#include <linux/errno.h>
+#include <linux/genetlink.h>
+#include <linux/gfp.h>
+#include <linux/if_ether.h>
+#include <linux/if_vlan.h>
+#include <linux/init.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/kernel.h>
+#include <linux/kref.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/printk.h>
+#include <linux/rculist.h>
+#include <linux/rcupdate.h>
+#include <linux/seq_file.h>
+#include <linux/skbuff.h>
+#include <linux/spinlock.h>
+#include <linux/stddef.h>
+#include <linux/string.h>
+#include <linux/workqueue.h>
+#include <net/dsfield.h>
+#include <net/rtnetlink.h>
+#include <uapi/linux/batadv_packet.h>
+#include <uapi/linux/batman_adv.h>
+
+#include "bat_algo.h"
+#include "bat_iv_ogm.h"
+#include "bat_v.h"
+#include "bridge_loop_avoidance.h"
+#include "debugfs.h"
+#include "distributed-arp-table.h"
+#include "gateway_client.h"
+#include "gateway_common.h"
+#include "hard-interface.h"
+#include "icmp_socket.h"
+#include "log.h"
+#include "multicast.h"
+#include "netlink.h"
+#include "network-coding.h"
+#include "originator.h"
+#include "routing.h"
+#include "send.h"
+#include "soft-interface.h"
+#include "tp_meter.h"
+#include "translation-table.h"
+
+/* List manipulations on hardif_list have to be rtnl_lock()'ed,
+ * list traversals just rcu-locked
+ */
+struct list_head batadv_hardif_list;
+static int (*batadv_rx_handler[256])(struct sk_buff *skb,
+ struct batadv_hard_iface *recv_if);
+
+unsigned char batadv_broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
+
+struct workqueue_struct *batadv_event_workqueue;
+
+static void batadv_recv_handler_init(void);
+
+static int __init batadv_init(void)
+{
+ int ret;
+
+ ret = batadv_tt_cache_init();
+ if (ret < 0)
+ return ret;
+
+ INIT_LIST_HEAD(&batadv_hardif_list);
+ batadv_algo_init();
+
+ batadv_recv_handler_init();
+
+ batadv_v_init();
+ batadv_iv_init();
+ batadv_nc_init();
+ batadv_tp_meter_init();
+
+ batadv_event_workqueue = create_singlethread_workqueue("bat_events");
+ if (!batadv_event_workqueue)
+ goto err_create_wq;
+
+ batadv_socket_init();
+ batadv_debugfs_init();
+
+ register_netdevice_notifier(&batadv_hard_if_notifier);
+ rtnl_link_register(&batadv_link_ops);
+ batadv_netlink_register();
+
+ pr_info("B.A.T.M.A.N. advanced %s (compatibility version %i) loaded\n",
+ BATADV_SOURCE_VERSION, BATADV_COMPAT_VERSION);
+
+ return 0;
+
+err_create_wq:
+ batadv_tt_cache_destroy();
+
+ return -ENOMEM;
+}
+
+static void __exit batadv_exit(void)
+{
+ batadv_debugfs_destroy();
+ batadv_netlink_unregister();
+ rtnl_link_unregister(&batadv_link_ops);
+ unregister_netdevice_notifier(&batadv_hard_if_notifier);
+ batadv_hardif_remove_interfaces();
+
+ flush_workqueue(batadv_event_workqueue);
+ destroy_workqueue(batadv_event_workqueue);
+ batadv_event_workqueue = NULL;
+
+ rcu_barrier();
+
+ batadv_tt_cache_destroy();
+}
+
+/**
+ * batadv_mesh_init() - Initialize soft interface
+ * @soft_iface: netdev struct of the soft interface
+ *
+ * Return: 0 on success or negative error number in case of failure
+ */
+int batadv_mesh_init(struct net_device *soft_iface)
+{
+ struct batadv_priv *bat_priv = netdev_priv(soft_iface);
+ int ret;
+
+ spin_lock_init(&bat_priv->forw_bat_list_lock);
+ spin_lock_init(&bat_priv->forw_bcast_list_lock);
+ spin_lock_init(&bat_priv->tt.changes_list_lock);
+ spin_lock_init(&bat_priv->tt.req_list_lock);
+ spin_lock_init(&bat_priv->tt.roam_list_lock);
+ spin_lock_init(&bat_priv->tt.last_changeset_lock);
+ spin_lock_init(&bat_priv->tt.commit_lock);
+ spin_lock_init(&bat_priv->gw.list_lock);
+#ifdef CONFIG_BATMAN_ADV_MCAST
+ spin_lock_init(&bat_priv->mcast.mla_lock);
+ spin_lock_init(&bat_priv->mcast.want_lists_lock);
+#endif
+ spin_lock_init(&bat_priv->tvlv.container_list_lock);
+ spin_lock_init(&bat_priv->tvlv.handler_list_lock);
+ spin_lock_init(&bat_priv->softif_vlan_list_lock);
+ spin_lock_init(&bat_priv->tp_list_lock);
+
+ INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
+ INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
+ INIT_HLIST_HEAD(&bat_priv->gw.gateway_list);
+#ifdef CONFIG_BATMAN_ADV_MCAST
+ INIT_HLIST_HEAD(&bat_priv->mcast.want_all_unsnoopables_list);
+ INIT_HLIST_HEAD(&bat_priv->mcast.want_all_ipv4_list);
+ INIT_HLIST_HEAD(&bat_priv->mcast.want_all_ipv6_list);
+#endif
+ INIT_LIST_HEAD(&bat_priv->tt.changes_list);
+ INIT_HLIST_HEAD(&bat_priv->tt.req_list);
+ INIT_LIST_HEAD(&bat_priv->tt.roam_list);
+#ifdef CONFIG_BATMAN_ADV_MCAST
+ INIT_HLIST_HEAD(&bat_priv->mcast.mla_list);
+#endif
+ INIT_HLIST_HEAD(&bat_priv->tvlv.container_list);
+ INIT_HLIST_HEAD(&bat_priv->tvlv.handler_list);
+ INIT_HLIST_HEAD(&bat_priv->softif_vlan_list);
+ INIT_HLIST_HEAD(&bat_priv->tp_list);
+
+ ret = batadv_originator_init(bat_priv);
+ if (ret < 0) {
+ atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);
+ goto err_orig;
+ }
+
+ ret = batadv_tt_init(bat_priv);
+ if (ret < 0) {
+ atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);
+ goto err_tt;
+ }
+
+ ret = batadv_v_mesh_init(bat_priv);
+ if (ret < 0) {
+ atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);
+ goto err_v;
+ }
+
+ ret = batadv_bla_init(bat_priv);
+ if (ret < 0) {
+ atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);
+ goto err_bla;
+ }
+
+ ret = batadv_dat_init(bat_priv);
+ if (ret < 0) {
+ atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);
+ goto err_dat;
+ }
+
+ ret = batadv_nc_mesh_init(bat_priv);
+ if (ret < 0) {
+ atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);
+ goto err_nc;
+ }
+
+ batadv_gw_init(bat_priv);
+ batadv_mcast_init(bat_priv);
+
+ atomic_set(&bat_priv->gw.reselect, 0);
+ atomic_set(&bat_priv->mesh_state, BATADV_MESH_ACTIVE);
+
+ return 0;
+
+err_nc:
+ batadv_dat_free(bat_priv);
+err_dat:
+ batadv_bla_free(bat_priv);
+err_bla:
+ batadv_v_mesh_free(bat_priv);
+err_v:
+ batadv_tt_free(bat_priv);
+err_tt:
+ batadv_originator_free(bat_priv);
+err_orig:
+ batadv_purge_outstanding_packets(bat_priv, NULL);
+ atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
+
+ return ret;
+}
+
+/**
+ * batadv_mesh_free() - Deinitialize soft interface
+ * @soft_iface: netdev struct of the soft interface
+ */
+void batadv_mesh_free(struct net_device *soft_iface)
+{
+ struct batadv_priv *bat_priv = netdev_priv(soft_iface);
+
+ atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);
+
+ batadv_purge_outstanding_packets(bat_priv, NULL);
+
+ batadv_gw_node_free(bat_priv);
+
+ batadv_v_mesh_free(bat_priv);
+ batadv_nc_mesh_free(bat_priv);
+ batadv_dat_free(bat_priv);
+ batadv_bla_free(bat_priv);
+
+ batadv_mcast_free(bat_priv);
+
+ /* Free the TT and the originator tables only after having terminated
+ * all the other depending components which may use these structures for
+ * their purposes.
+ */
+ batadv_tt_free(bat_priv);
+
+ /* Since the originator table clean up routine is accessing the TT
+ * tables as well, it has to be invoked after the TT tables have been
+ * freed and marked as empty. This ensures that no cleanup RCU callbacks
+ * accessing the TT data are scheduled for later execution.
+ */
+ batadv_originator_free(bat_priv);
+
+ batadv_gw_free(bat_priv);
+
+ free_percpu(bat_priv->bat_counters);
+ bat_priv->bat_counters = NULL;
+
+ atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
+}
+
+/**
+ * batadv_is_my_mac() - check if the given mac address belongs to any of the
+ * real interfaces in the current mesh
+ * @bat_priv: the bat priv with all the soft interface information
+ * @addr: the address to check
+ *
+ * Return: 'true' if the mac address was found, false otherwise.
+ */
+bool batadv_is_my_mac(struct batadv_priv *bat_priv, const u8 *addr)
+{
+ const struct batadv_hard_iface *hard_iface;
+ bool is_my_mac = false;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
+ if (hard_iface->if_status != BATADV_IF_ACTIVE)
+ continue;
+
+ if (hard_iface->soft_iface != bat_priv->soft_iface)
+ continue;
+
+ if (batadv_compare_eth(hard_iface->net_dev->dev_addr, addr)) {
+ is_my_mac = true;
+ break;
+ }
+ }
+ rcu_read_unlock();
+ return is_my_mac;
+}
+
+#ifdef CONFIG_BATMAN_ADV_DEBUGFS
+/**
+ * batadv_seq_print_text_primary_if_get() - called from debugfs table printing
+ * function that requires the primary interface
+ * @seq: debugfs table seq_file struct
+ *
+ * Return: primary interface if found or NULL otherwise.
+ */
+struct batadv_hard_iface *
+batadv_seq_print_text_primary_if_get(struct seq_file *seq)
+{
+ struct net_device *net_dev = (struct net_device *)seq->private;
+ struct batadv_priv *bat_priv = netdev_priv(net_dev);
+ struct batadv_hard_iface *primary_if;
+
+ primary_if = batadv_primary_if_get_selected(bat_priv);
+
+ if (!primary_if) {
+ seq_printf(seq,
+ "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
+ net_dev->name);
+ goto out;
+ }
+
+ if (primary_if->if_status == BATADV_IF_ACTIVE)
+ goto out;
+
+ seq_printf(seq,
+ "BATMAN mesh %s disabled - primary interface not active\n",
+ net_dev->name);
+ batadv_hardif_put(primary_if);
+ primary_if = NULL;
+
+out:
+ return primary_if;
+}
+#endif
+
+/**
+ * batadv_max_header_len() - calculate maximum encapsulation overhead for a
+ * payload packet
+ *
+ * Return: the maximum encapsulation overhead in bytes.
+ */
+int batadv_max_header_len(void)
+{
+ int header_len = 0;
+
+ header_len = max_t(int, header_len,
+ sizeof(struct batadv_unicast_packet));
+ header_len = max_t(int, header_len,
+ sizeof(struct batadv_unicast_4addr_packet));
+ header_len = max_t(int, header_len,
+ sizeof(struct batadv_bcast_packet));
+
+#ifdef CONFIG_BATMAN_ADV_NC
+ header_len = max_t(int, header_len,
+ sizeof(struct batadv_coded_packet));
+#endif
+
+ return header_len + ETH_HLEN;
+}
+
+/**
+ * batadv_skb_set_priority() - sets skb priority according to packet content
+ * @skb: the packet to be sent
+ * @offset: offset to the packet content
+ *
+ * This function sets a value between 256 and 263 (802.1d priority), which
+ * can be interpreted by the cfg80211 or other drivers.
+ */
+void batadv_skb_set_priority(struct sk_buff *skb, int offset)
+{
+ struct iphdr ip_hdr_tmp, *ip_hdr;
+ struct ipv6hdr ip6_hdr_tmp, *ip6_hdr;
+ struct ethhdr ethhdr_tmp, *ethhdr;
+ struct vlan_ethhdr *vhdr, vhdr_tmp;
+ u32 prio;
+
+ /* already set, do nothing */
+ if (skb->priority >= 256 && skb->priority <= 263)
+ return;
+
+ ethhdr = skb_header_pointer(skb, offset, sizeof(*ethhdr), &ethhdr_tmp);
+ if (!ethhdr)
+ return;
+
+ switch (ethhdr->h_proto) {
+ case htons(ETH_P_8021Q):
+ vhdr = skb_header_pointer(skb, offset + sizeof(*vhdr),
+ sizeof(*vhdr), &vhdr_tmp);
+ if (!vhdr)
+ return;
+ prio = ntohs(vhdr->h_vlan_TCI) & VLAN_PRIO_MASK;
+ prio = prio >> VLAN_PRIO_SHIFT;
+ break;
+ case htons(ETH_P_IP):
+ ip_hdr = skb_header_pointer(skb, offset + sizeof(*ethhdr),
+ sizeof(*ip_hdr), &ip_hdr_tmp);
+ if (!ip_hdr)
+ return;
+ prio = (ipv4_get_dsfield(ip_hdr) & 0xfc) >> 5;
+ break;
+ case htons(ETH_P_IPV6):
+ ip6_hdr = skb_header_pointer(skb, offset + sizeof(*ethhdr),
+ sizeof(*ip6_hdr), &ip6_hdr_tmp);
+ if (!ip6_hdr)
+ return;
+ prio = (ipv6_get_dsfield(ip6_hdr) & 0xfc) >> 5;
+ break;
+ default:
+ return;
+ }
+
+ skb->priority = prio + 256;
+}
+
+static int batadv_recv_unhandled_packet(struct sk_buff *skb,
+ struct batadv_hard_iface *recv_if)
+{
+ kfree_skb(skb);
+
+ return NET_RX_DROP;
+}
+
+/* incoming packets with the batman ethertype received on any active hard
+ * interface
+ */
+
+/**
+ * batadv_batman_skb_recv() - Handle incoming message from an hard interface
+ * @skb: the received packet
+ * @dev: the net device that the packet was received on
+ * @ptype: packet type of incoming packet (ETH_P_BATMAN)
+ * @orig_dev: the original receive net device (e.g. bonded device)
+ *
+ * Return: NET_RX_SUCCESS on success or NET_RX_DROP in case of failure
+ */
+int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *ptype,
+ struct net_device *orig_dev)
+{
+ struct batadv_priv *bat_priv;
+ struct batadv_ogm_packet *batadv_ogm_packet;
+ struct batadv_hard_iface *hard_iface;
+ u8 idx;
+
+ hard_iface = container_of(ptype, struct batadv_hard_iface,
+ batman_adv_ptype);
+
+ /* Prevent processing a packet received on an interface which is getting
+ * shut down otherwise the packet may trigger de-reference errors
+ * further down in the receive path.
+ */
+ if (!kref_get_unless_zero(&hard_iface->refcount))
+ goto err_out;
+
+ skb = skb_share_check(skb, GFP_ATOMIC);
+
+ /* skb was released by skb_share_check() */
+ if (!skb)
+ goto err_put;
+
+ /* packet should hold at least type and version */
+ if (unlikely(!pskb_may_pull(skb, 2)))
+ goto err_free;
+
+ /* expect a valid ethernet header here. */
+ if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb)))
+ goto err_free;
+
+ if (!hard_iface->soft_iface)
+ goto err_free;
+
+ bat_priv = netdev_priv(hard_iface->soft_iface);
+
+ if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
+ goto err_free;
+
+ /* discard frames on not active interfaces */
+ if (hard_iface->if_status != BATADV_IF_ACTIVE)
+ goto err_free;
+
+ batadv_ogm_packet = (struct batadv_ogm_packet *)skb->data;
+
+ if (batadv_ogm_packet->version != BATADV_COMPAT_VERSION) {
+ batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+ "Drop packet: incompatible batman version (%i)\n",
+ batadv_ogm_packet->version);
+ goto err_free;
+ }
+
+ /* reset control block to avoid left overs from previous users */
+ memset(skb->cb, 0, sizeof(struct batadv_skb_cb));
+
+ idx = batadv_ogm_packet->packet_type;
+ (*batadv_rx_handler[idx])(skb, hard_iface);
+
+ batadv_hardif_put(hard_iface);
+
+ /* return NET_RX_SUCCESS in any case as we
+ * most probably dropped the packet for
+ * routing-logical reasons.
+ */
+ return NET_RX_SUCCESS;
+
+err_free:
+ kfree_skb(skb);
+err_put:
+ batadv_hardif_put(hard_iface);
+err_out:
+ return NET_RX_DROP;
+}
+
+static void batadv_recv_handler_init(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(batadv_rx_handler); i++)
+ batadv_rx_handler[i] = batadv_recv_unhandled_packet;
+
+ for (i = BATADV_UNICAST_MIN; i <= BATADV_UNICAST_MAX; i++)
+ batadv_rx_handler[i] = batadv_recv_unhandled_unicast_packet;
+
+ /* compile time checks for sizes */
+ BUILD_BUG_ON(sizeof(struct batadv_bla_claim_dst) != 6);
+ BUILD_BUG_ON(sizeof(struct batadv_ogm_packet) != 24);
+ BUILD_BUG_ON(sizeof(struct batadv_icmp_header) != 20);
+ BUILD_BUG_ON(sizeof(struct batadv_icmp_packet) != 20);
+ BUILD_BUG_ON(sizeof(struct batadv_icmp_packet_rr) != 116);
+ BUILD_BUG_ON(sizeof(struct batadv_unicast_packet) != 10);
+ BUILD_BUG_ON(sizeof(struct batadv_unicast_4addr_packet) != 18);
+ BUILD_BUG_ON(sizeof(struct batadv_frag_packet) != 20);
+ BUILD_BUG_ON(sizeof(struct batadv_bcast_packet) != 14);
+ BUILD_BUG_ON(sizeof(struct batadv_coded_packet) != 46);
+ BUILD_BUG_ON(sizeof(struct batadv_unicast_tvlv_packet) != 20);
+ BUILD_BUG_ON(sizeof(struct batadv_tvlv_hdr) != 4);
+ BUILD_BUG_ON(sizeof(struct batadv_tvlv_gateway_data) != 8);
+ BUILD_BUG_ON(sizeof(struct batadv_tvlv_tt_vlan_data) != 8);
+ BUILD_BUG_ON(sizeof(struct batadv_tvlv_tt_change) != 12);
+ BUILD_BUG_ON(sizeof(struct batadv_tvlv_roam_adv) != 8);
+
+ i = FIELD_SIZEOF(struct sk_buff, cb);
+ BUILD_BUG_ON(sizeof(struct batadv_skb_cb) > i);
+
+ /* broadcast packet */
+ batadv_rx_handler[BATADV_BCAST] = batadv_recv_bcast_packet;
+
+ /* unicast packets ... */
+ /* unicast with 4 addresses packet */
+ batadv_rx_handler[BATADV_UNICAST_4ADDR] = batadv_recv_unicast_packet;
+ /* unicast packet */
+ batadv_rx_handler[BATADV_UNICAST] = batadv_recv_unicast_packet;
+ /* unicast tvlv packet */
+ batadv_rx_handler[BATADV_UNICAST_TVLV] = batadv_recv_unicast_tvlv;
+ /* batman icmp packet */
+ batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet;
+ /* Fragmented packets */
+ batadv_rx_handler[BATADV_UNICAST_FRAG] = batadv_recv_frag_packet;
+}
+
+/**
+ * batadv_recv_handler_register() - Register handler for batman-adv packet type
+ * @packet_type: batadv_packettype which should be handled
+ * @recv_handler: receive handler for the packet type
+ *
+ * Return: 0 on success or negative error number in case of failure
+ */
+int
+batadv_recv_handler_register(u8 packet_type,
+ int (*recv_handler)(struct sk_buff *,
+ struct batadv_hard_iface *))
+{
+ int (*curr)(struct sk_buff *skb,
+ struct batadv_hard_iface *recv_if);
+ curr = batadv_rx_handler[packet_type];
+
+ if (curr != batadv_recv_unhandled_packet &&
+ curr != batadv_recv_unhandled_unicast_packet)
+ return -EBUSY;
+
+ batadv_rx_handler[packet_type] = recv_handler;
+ return 0;
+}
+
+/**
+ * batadv_recv_handler_unregister() - Unregister handler for packet type
+ * @packet_type: batadv_packettype which should no longer be handled
+ */
+void batadv_recv_handler_unregister(u8 packet_type)
+{
+ batadv_rx_handler[packet_type] = batadv_recv_unhandled_packet;
+}
+
+/**
+ * batadv_skb_crc32() - calculate CRC32 of the whole packet and skip bytes in
+ * the header
+ * @skb: skb pointing to fragmented socket buffers
+ * @payload_ptr: Pointer to position inside the head buffer of the skb
+ * marking the start of the data to be CRC'ed
+ *
+ * payload_ptr must always point to an address in the skb head buffer and not to
+ * a fragment.
+ *
+ * Return: big endian crc32c of the checksummed data
+ */
+__be32 batadv_skb_crc32(struct sk_buff *skb, u8 *payload_ptr)
+{
+ u32 crc = 0;
+ unsigned int from;
+ unsigned int to = skb->len;
+ struct skb_seq_state st;
+ const u8 *data;
+ unsigned int len;
+ unsigned int consumed = 0;
+
+ from = (unsigned int)(payload_ptr - skb->data);
+
+ skb_prepare_seq_read(skb, from, to, &st);
+ while ((len = skb_seq_read(consumed, &data, &st)) != 0) {
+ crc = crc32c(crc, data, len);
+ consumed += len;
+ }
+
+ return htonl(crc);
+}
+
+/**
+ * batadv_get_vid() - extract the VLAN identifier from skb if any
+ * @skb: the buffer containing the packet
+ * @header_len: length of the batman header preceding the ethernet header
+ *
+ * Return: VID with the BATADV_VLAN_HAS_TAG flag when the packet embedded in the
+ * skb is vlan tagged. Otherwise BATADV_NO_FLAGS.
+ */
+unsigned short batadv_get_vid(struct sk_buff *skb, size_t header_len)
+{
+ struct ethhdr *ethhdr = (struct ethhdr *)(skb->data + header_len);
+ struct vlan_ethhdr *vhdr;
+ unsigned short vid;
+
+ if (ethhdr->h_proto != htons(ETH_P_8021Q))
+ return BATADV_NO_FLAGS;
+
+ if (!pskb_may_pull(skb, header_len + VLAN_ETH_HLEN))
+ return BATADV_NO_FLAGS;
+
+ vhdr = (struct vlan_ethhdr *)(skb->data + header_len);
+ vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;
+ vid |= BATADV_VLAN_HAS_TAG;
+
+ return vid;
+}
+
+/**
+ * batadv_vlan_ap_isola_get() - return AP isolation status for the given vlan
+ * @bat_priv: the bat priv with all the soft interface information
+ * @vid: the VLAN identifier for which the AP isolation attributed as to be
+ * looked up
+ *
+ * Return: true if AP isolation is on for the VLAN idenfied by vid, false
+ * otherwise
+ */
+bool batadv_vlan_ap_isola_get(struct batadv_priv *bat_priv, unsigned short vid)
+{
+ bool ap_isolation_enabled = false;
+ struct batadv_softif_vlan *vlan;
+
+ /* if the AP isolation is requested on a VLAN, then check for its
+ * setting in the proper VLAN private data structure
+ */
+ vlan = batadv_softif_vlan_get(bat_priv, vid);
+ if (vlan) {
+ ap_isolation_enabled = atomic_read(&vlan->ap_isolation);
+ batadv_softif_vlan_put(vlan);
+ }
+
+ return ap_isolation_enabled;
+}
+
+module_init(batadv_init);
+module_exit(batadv_exit);
+
+MODULE_LICENSE("GPL");
+
+MODULE_AUTHOR(BATADV_DRIVER_AUTHOR);
+MODULE_DESCRIPTION(BATADV_DRIVER_DESC);
+MODULE_SUPPORTED_DEVICE(BATADV_DRIVER_DEVICE);
+MODULE_VERSION(BATADV_SOURCE_VERSION);
+MODULE_ALIAS_RTNL_LINK("batadv");
+MODULE_ALIAS_GENL_FAMILY(BATADV_NL_NAME);