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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /net/batman-adv/bridge_loop_avoidance.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/batman-adv/bridge_loop_avoidance.c')
-rw-r--r--net/batman-adv/bridge_loop_avoidance.c2502
1 files changed, 2502 insertions, 0 deletions
diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c
new file mode 100644
index 000000000..37ce6cfb3
--- /dev/null
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -0,0 +1,2502 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) B.A.T.M.A.N. contributors:
+ *
+ * Simon Wunderlich
+ */
+
+#include "bridge_loop_avoidance.h"
+#include "main.h"
+
+#include <linux/atomic.h>
+#include <linux/byteorder/generic.h>
+#include <linux/compiler.h>
+#include <linux/container_of.h>
+#include <linux/crc16.h>
+#include <linux/errno.h>
+#include <linux/etherdevice.h>
+#include <linux/gfp.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/if_vlan.h>
+#include <linux/jhash.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/kref.h>
+#include <linux/list.h>
+#include <linux/lockdep.h>
+#include <linux/netdevice.h>
+#include <linux/netlink.h>
+#include <linux/rculist.h>
+#include <linux/rcupdate.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/stddef.h>
+#include <linux/string.h>
+#include <linux/workqueue.h>
+#include <net/arp.h>
+#include <net/genetlink.h>
+#include <net/netlink.h>
+#include <net/sock.h>
+#include <uapi/linux/batadv_packet.h>
+#include <uapi/linux/batman_adv.h>
+
+#include "hard-interface.h"
+#include "hash.h"
+#include "log.h"
+#include "netlink.h"
+#include "originator.h"
+#include "soft-interface.h"
+#include "translation-table.h"
+
+static const u8 batadv_announce_mac[4] = {0x43, 0x05, 0x43, 0x05};
+
+static void batadv_bla_periodic_work(struct work_struct *work);
+static void
+batadv_bla_send_announce(struct batadv_priv *bat_priv,
+ struct batadv_bla_backbone_gw *backbone_gw);
+
+/**
+ * batadv_choose_claim() - choose the right bucket for a claim.
+ * @data: data to hash
+ * @size: size of the hash table
+ *
+ * Return: the hash index of the claim
+ */
+static inline u32 batadv_choose_claim(const void *data, u32 size)
+{
+ const struct batadv_bla_claim *claim = data;
+ u32 hash = 0;
+
+ hash = jhash(&claim->addr, sizeof(claim->addr), hash);
+ hash = jhash(&claim->vid, sizeof(claim->vid), hash);
+
+ return hash % size;
+}
+
+/**
+ * batadv_choose_backbone_gw() - choose the right bucket for a backbone gateway.
+ * @data: data to hash
+ * @size: size of the hash table
+ *
+ * Return: the hash index of the backbone gateway
+ */
+static inline u32 batadv_choose_backbone_gw(const void *data, u32 size)
+{
+ const struct batadv_bla_backbone_gw *gw;
+ u32 hash = 0;
+
+ gw = data;
+ hash = jhash(&gw->orig, sizeof(gw->orig), hash);
+ hash = jhash(&gw->vid, sizeof(gw->vid), hash);
+
+ return hash % size;
+}
+
+/**
+ * batadv_compare_backbone_gw() - compare address and vid of two backbone gws
+ * @node: list node of the first entry to compare
+ * @data2: pointer to the second backbone gateway
+ *
+ * Return: true if the backbones have the same data, false otherwise
+ */
+static bool batadv_compare_backbone_gw(const struct hlist_node *node,
+ const void *data2)
+{
+ const void *data1 = container_of(node, struct batadv_bla_backbone_gw,
+ hash_entry);
+ const struct batadv_bla_backbone_gw *gw1 = data1;
+ const struct batadv_bla_backbone_gw *gw2 = data2;
+
+ if (!batadv_compare_eth(gw1->orig, gw2->orig))
+ return false;
+
+ if (gw1->vid != gw2->vid)
+ return false;
+
+ return true;
+}
+
+/**
+ * batadv_compare_claim() - compare address and vid of two claims
+ * @node: list node of the first entry to compare
+ * @data2: pointer to the second claims
+ *
+ * Return: true if the claim have the same data, 0 otherwise
+ */
+static bool batadv_compare_claim(const struct hlist_node *node,
+ const void *data2)
+{
+ const void *data1 = container_of(node, struct batadv_bla_claim,
+ hash_entry);
+ const struct batadv_bla_claim *cl1 = data1;
+ const struct batadv_bla_claim *cl2 = data2;
+
+ if (!batadv_compare_eth(cl1->addr, cl2->addr))
+ return false;
+
+ if (cl1->vid != cl2->vid)
+ return false;
+
+ return true;
+}
+
+/**
+ * batadv_backbone_gw_release() - release backbone gw from lists and queue for
+ * free after rcu grace period
+ * @ref: kref pointer of the backbone gw
+ */
+static void batadv_backbone_gw_release(struct kref *ref)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+
+ backbone_gw = container_of(ref, struct batadv_bla_backbone_gw,
+ refcount);
+
+ kfree_rcu(backbone_gw, rcu);
+}
+
+/**
+ * batadv_backbone_gw_put() - decrement the backbone gw refcounter and possibly
+ * release it
+ * @backbone_gw: backbone gateway to be free'd
+ */
+static void batadv_backbone_gw_put(struct batadv_bla_backbone_gw *backbone_gw)
+{
+ if (!backbone_gw)
+ return;
+
+ kref_put(&backbone_gw->refcount, batadv_backbone_gw_release);
+}
+
+/**
+ * batadv_claim_release() - release claim from lists and queue for free after
+ * rcu grace period
+ * @ref: kref pointer of the claim
+ */
+static void batadv_claim_release(struct kref *ref)
+{
+ struct batadv_bla_claim *claim;
+ struct batadv_bla_backbone_gw *old_backbone_gw;
+
+ claim = container_of(ref, struct batadv_bla_claim, refcount);
+
+ spin_lock_bh(&claim->backbone_lock);
+ old_backbone_gw = claim->backbone_gw;
+ claim->backbone_gw = NULL;
+ spin_unlock_bh(&claim->backbone_lock);
+
+ spin_lock_bh(&old_backbone_gw->crc_lock);
+ old_backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN);
+ spin_unlock_bh(&old_backbone_gw->crc_lock);
+
+ batadv_backbone_gw_put(old_backbone_gw);
+
+ kfree_rcu(claim, rcu);
+}
+
+/**
+ * batadv_claim_put() - decrement the claim refcounter and possibly release it
+ * @claim: claim to be free'd
+ */
+static void batadv_claim_put(struct batadv_bla_claim *claim)
+{
+ if (!claim)
+ return;
+
+ kref_put(&claim->refcount, batadv_claim_release);
+}
+
+/**
+ * batadv_claim_hash_find() - looks for a claim in the claim hash
+ * @bat_priv: the bat priv with all the soft interface information
+ * @data: search data (may be local/static data)
+ *
+ * Return: claim if found or NULL otherwise.
+ */
+static struct batadv_bla_claim *
+batadv_claim_hash_find(struct batadv_priv *bat_priv,
+ struct batadv_bla_claim *data)
+{
+ struct batadv_hashtable *hash = bat_priv->bla.claim_hash;
+ struct hlist_head *head;
+ struct batadv_bla_claim *claim;
+ struct batadv_bla_claim *claim_tmp = NULL;
+ int index;
+
+ if (!hash)
+ return NULL;
+
+ index = batadv_choose_claim(data, hash->size);
+ head = &hash->table[index];
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(claim, head, hash_entry) {
+ if (!batadv_compare_claim(&claim->hash_entry, data))
+ continue;
+
+ if (!kref_get_unless_zero(&claim->refcount))
+ continue;
+
+ claim_tmp = claim;
+ break;
+ }
+ rcu_read_unlock();
+
+ return claim_tmp;
+}
+
+/**
+ * batadv_backbone_hash_find() - looks for a backbone gateway in the hash
+ * @bat_priv: the bat priv with all the soft interface information
+ * @addr: the address of the originator
+ * @vid: the VLAN ID
+ *
+ * Return: backbone gateway if found or NULL otherwise
+ */
+static struct batadv_bla_backbone_gw *
+batadv_backbone_hash_find(struct batadv_priv *bat_priv, const u8 *addr,
+ unsigned short vid)
+{
+ struct batadv_hashtable *hash = bat_priv->bla.backbone_hash;
+ struct hlist_head *head;
+ struct batadv_bla_backbone_gw search_entry, *backbone_gw;
+ struct batadv_bla_backbone_gw *backbone_gw_tmp = NULL;
+ int index;
+
+ if (!hash)
+ return NULL;
+
+ ether_addr_copy(search_entry.orig, addr);
+ search_entry.vid = vid;
+
+ index = batadv_choose_backbone_gw(&search_entry, hash->size);
+ head = &hash->table[index];
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(backbone_gw, head, hash_entry) {
+ if (!batadv_compare_backbone_gw(&backbone_gw->hash_entry,
+ &search_entry))
+ continue;
+
+ if (!kref_get_unless_zero(&backbone_gw->refcount))
+ continue;
+
+ backbone_gw_tmp = backbone_gw;
+ break;
+ }
+ rcu_read_unlock();
+
+ return backbone_gw_tmp;
+}
+
+/**
+ * batadv_bla_del_backbone_claims() - delete all claims for a backbone
+ * @backbone_gw: backbone gateway where the claims should be removed
+ */
+static void
+batadv_bla_del_backbone_claims(struct batadv_bla_backbone_gw *backbone_gw)
+{
+ struct batadv_hashtable *hash;
+ struct hlist_node *node_tmp;
+ struct hlist_head *head;
+ struct batadv_bla_claim *claim;
+ int i;
+ spinlock_t *list_lock; /* protects write access to the hash lists */
+
+ hash = backbone_gw->bat_priv->bla.claim_hash;
+ if (!hash)
+ return;
+
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+ list_lock = &hash->list_locks[i];
+
+ spin_lock_bh(list_lock);
+ hlist_for_each_entry_safe(claim, node_tmp,
+ head, hash_entry) {
+ if (claim->backbone_gw != backbone_gw)
+ continue;
+
+ batadv_claim_put(claim);
+ hlist_del_rcu(&claim->hash_entry);
+ }
+ spin_unlock_bh(list_lock);
+ }
+
+ /* all claims gone, initialize CRC */
+ spin_lock_bh(&backbone_gw->crc_lock);
+ backbone_gw->crc = BATADV_BLA_CRC_INIT;
+ spin_unlock_bh(&backbone_gw->crc_lock);
+}
+
+/**
+ * batadv_bla_send_claim() - sends a claim frame according to the provided info
+ * @bat_priv: the bat priv with all the soft interface information
+ * @mac: the mac address to be announced within the claim
+ * @vid: the VLAN ID
+ * @claimtype: the type of the claim (CLAIM, UNCLAIM, ANNOUNCE, ...)
+ */
+static void batadv_bla_send_claim(struct batadv_priv *bat_priv, const u8 *mac,
+ unsigned short vid, int claimtype)
+{
+ struct sk_buff *skb;
+ struct ethhdr *ethhdr;
+ struct batadv_hard_iface *primary_if;
+ struct net_device *soft_iface;
+ u8 *hw_src;
+ struct batadv_bla_claim_dst local_claim_dest;
+ __be32 zeroip = 0;
+
+ primary_if = batadv_primary_if_get_selected(bat_priv);
+ if (!primary_if)
+ return;
+
+ memcpy(&local_claim_dest, &bat_priv->bla.claim_dest,
+ sizeof(local_claim_dest));
+ local_claim_dest.type = claimtype;
+
+ soft_iface = primary_if->soft_iface;
+
+ skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
+ /* IP DST: 0.0.0.0 */
+ zeroip,
+ primary_if->soft_iface,
+ /* IP SRC: 0.0.0.0 */
+ zeroip,
+ /* Ethernet DST: Broadcast */
+ NULL,
+ /* Ethernet SRC/HW SRC: originator mac */
+ primary_if->net_dev->dev_addr,
+ /* HW DST: FF:43:05:XX:YY:YY
+ * with XX = claim type
+ * and YY:YY = group id
+ */
+ (u8 *)&local_claim_dest);
+
+ if (!skb)
+ goto out;
+
+ ethhdr = (struct ethhdr *)skb->data;
+ hw_src = (u8 *)ethhdr + ETH_HLEN + sizeof(struct arphdr);
+
+ /* now we pretend that the client would have sent this ... */
+ switch (claimtype) {
+ case BATADV_CLAIM_TYPE_CLAIM:
+ /* normal claim frame
+ * set Ethernet SRC to the clients mac
+ */
+ ether_addr_copy(ethhdr->h_source, mac);
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): CLAIM %pM on vid %d\n", __func__, mac,
+ batadv_print_vid(vid));
+ break;
+ case BATADV_CLAIM_TYPE_UNCLAIM:
+ /* unclaim frame
+ * set HW SRC to the clients mac
+ */
+ ether_addr_copy(hw_src, mac);
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): UNCLAIM %pM on vid %d\n", __func__, mac,
+ batadv_print_vid(vid));
+ break;
+ case BATADV_CLAIM_TYPE_ANNOUNCE:
+ /* announcement frame
+ * set HW SRC to the special mac containing the crc
+ */
+ ether_addr_copy(hw_src, mac);
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): ANNOUNCE of %pM on vid %d\n", __func__,
+ ethhdr->h_source, batadv_print_vid(vid));
+ break;
+ case BATADV_CLAIM_TYPE_REQUEST:
+ /* request frame
+ * set HW SRC and header destination to the receiving backbone
+ * gws mac
+ */
+ ether_addr_copy(hw_src, mac);
+ ether_addr_copy(ethhdr->h_dest, mac);
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): REQUEST of %pM to %pM on vid %d\n", __func__,
+ ethhdr->h_source, ethhdr->h_dest,
+ batadv_print_vid(vid));
+ break;
+ case BATADV_CLAIM_TYPE_LOOPDETECT:
+ ether_addr_copy(ethhdr->h_source, mac);
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): LOOPDETECT of %pM to %pM on vid %d\n",
+ __func__, ethhdr->h_source, ethhdr->h_dest,
+ batadv_print_vid(vid));
+
+ break;
+ }
+
+ if (vid & BATADV_VLAN_HAS_TAG) {
+ skb = vlan_insert_tag(skb, htons(ETH_P_8021Q),
+ vid & VLAN_VID_MASK);
+ if (!skb)
+ goto out;
+ }
+
+ skb_reset_mac_header(skb);
+ skb->protocol = eth_type_trans(skb, soft_iface);
+ batadv_inc_counter(bat_priv, BATADV_CNT_RX);
+ batadv_add_counter(bat_priv, BATADV_CNT_RX_BYTES,
+ skb->len + ETH_HLEN);
+
+ netif_rx(skb);
+out:
+ batadv_hardif_put(primary_if);
+}
+
+/**
+ * batadv_bla_loopdetect_report() - worker for reporting the loop
+ * @work: work queue item
+ *
+ * Throws an uevent, as the loopdetect check function can't do that itself
+ * since the kernel may sleep while throwing uevents.
+ */
+static void batadv_bla_loopdetect_report(struct work_struct *work)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+ struct batadv_priv *bat_priv;
+ char vid_str[6] = { '\0' };
+
+ backbone_gw = container_of(work, struct batadv_bla_backbone_gw,
+ report_work);
+ bat_priv = backbone_gw->bat_priv;
+
+ batadv_info(bat_priv->soft_iface,
+ "Possible loop on VLAN %d detected which can't be handled by BLA - please check your network setup!\n",
+ batadv_print_vid(backbone_gw->vid));
+ snprintf(vid_str, sizeof(vid_str), "%d",
+ batadv_print_vid(backbone_gw->vid));
+ vid_str[sizeof(vid_str) - 1] = 0;
+
+ batadv_throw_uevent(bat_priv, BATADV_UEV_BLA, BATADV_UEV_LOOPDETECT,
+ vid_str);
+
+ batadv_backbone_gw_put(backbone_gw);
+}
+
+/**
+ * batadv_bla_get_backbone_gw() - finds or creates a backbone gateway
+ * @bat_priv: the bat priv with all the soft interface information
+ * @orig: the mac address of the originator
+ * @vid: the VLAN ID
+ * @own_backbone: set if the requested backbone is local
+ *
+ * Return: the (possibly created) backbone gateway or NULL on error
+ */
+static struct batadv_bla_backbone_gw *
+batadv_bla_get_backbone_gw(struct batadv_priv *bat_priv, const u8 *orig,
+ unsigned short vid, bool own_backbone)
+{
+ struct batadv_bla_backbone_gw *entry;
+ struct batadv_orig_node *orig_node;
+ int hash_added;
+
+ entry = batadv_backbone_hash_find(bat_priv, orig, vid);
+
+ if (entry)
+ return entry;
+
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): not found (%pM, %d), creating new entry\n", __func__,
+ orig, batadv_print_vid(vid));
+
+ entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
+ if (!entry)
+ return NULL;
+
+ entry->vid = vid;
+ entry->lasttime = jiffies;
+ entry->crc = BATADV_BLA_CRC_INIT;
+ entry->bat_priv = bat_priv;
+ spin_lock_init(&entry->crc_lock);
+ atomic_set(&entry->request_sent, 0);
+ atomic_set(&entry->wait_periods, 0);
+ ether_addr_copy(entry->orig, orig);
+ INIT_WORK(&entry->report_work, batadv_bla_loopdetect_report);
+ kref_init(&entry->refcount);
+
+ kref_get(&entry->refcount);
+ hash_added = batadv_hash_add(bat_priv->bla.backbone_hash,
+ batadv_compare_backbone_gw,
+ batadv_choose_backbone_gw, entry,
+ &entry->hash_entry);
+
+ if (unlikely(hash_added != 0)) {
+ /* hash failed, free the structure */
+ kfree(entry);
+ return NULL;
+ }
+
+ /* this is a gateway now, remove any TT entry on this VLAN */
+ orig_node = batadv_orig_hash_find(bat_priv, orig);
+ if (orig_node) {
+ batadv_tt_global_del_orig(bat_priv, orig_node, vid,
+ "became a backbone gateway");
+ batadv_orig_node_put(orig_node);
+ }
+
+ if (own_backbone) {
+ batadv_bla_send_announce(bat_priv, entry);
+
+ /* this will be decreased in the worker thread */
+ atomic_inc(&entry->request_sent);
+ atomic_set(&entry->wait_periods, BATADV_BLA_WAIT_PERIODS);
+ atomic_inc(&bat_priv->bla.num_requests);
+ }
+
+ return entry;
+}
+
+/**
+ * batadv_bla_update_own_backbone_gw() - updates the own backbone gw for a VLAN
+ * @bat_priv: the bat priv with all the soft interface information
+ * @primary_if: the selected primary interface
+ * @vid: VLAN identifier
+ *
+ * update or add the own backbone gw to make sure we announce
+ * where we receive other backbone gws
+ */
+static void
+batadv_bla_update_own_backbone_gw(struct batadv_priv *bat_priv,
+ struct batadv_hard_iface *primary_if,
+ unsigned short vid)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+
+ backbone_gw = batadv_bla_get_backbone_gw(bat_priv,
+ primary_if->net_dev->dev_addr,
+ vid, true);
+ if (unlikely(!backbone_gw))
+ return;
+
+ backbone_gw->lasttime = jiffies;
+ batadv_backbone_gw_put(backbone_gw);
+}
+
+/**
+ * batadv_bla_answer_request() - answer a bla request by sending own claims
+ * @bat_priv: the bat priv with all the soft interface information
+ * @primary_if: interface where the request came on
+ * @vid: the vid where the request came on
+ *
+ * Repeat all of our own claims, and finally send an ANNOUNCE frame
+ * to allow the requester another check if the CRC is correct now.
+ */
+static void batadv_bla_answer_request(struct batadv_priv *bat_priv,
+ struct batadv_hard_iface *primary_if,
+ unsigned short vid)
+{
+ struct hlist_head *head;
+ struct batadv_hashtable *hash;
+ struct batadv_bla_claim *claim;
+ struct batadv_bla_backbone_gw *backbone_gw;
+ int i;
+
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): received a claim request, send all of our own claims again\n",
+ __func__);
+
+ backbone_gw = batadv_backbone_hash_find(bat_priv,
+ primary_if->net_dev->dev_addr,
+ vid);
+ if (!backbone_gw)
+ return;
+
+ hash = bat_priv->bla.claim_hash;
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(claim, head, hash_entry) {
+ /* only own claims are interesting */
+ if (claim->backbone_gw != backbone_gw)
+ continue;
+
+ batadv_bla_send_claim(bat_priv, claim->addr, claim->vid,
+ BATADV_CLAIM_TYPE_CLAIM);
+ }
+ rcu_read_unlock();
+ }
+
+ /* finally, send an announcement frame */
+ batadv_bla_send_announce(bat_priv, backbone_gw);
+ batadv_backbone_gw_put(backbone_gw);
+}
+
+/**
+ * batadv_bla_send_request() - send a request to repeat claims
+ * @backbone_gw: the backbone gateway from whom we are out of sync
+ *
+ * When the crc is wrong, ask the backbone gateway for a full table update.
+ * After the request, it will repeat all of his own claims and finally
+ * send an announcement claim with which we can check again.
+ */
+static void batadv_bla_send_request(struct batadv_bla_backbone_gw *backbone_gw)
+{
+ /* first, remove all old entries */
+ batadv_bla_del_backbone_claims(backbone_gw);
+
+ batadv_dbg(BATADV_DBG_BLA, backbone_gw->bat_priv,
+ "Sending REQUEST to %pM\n", backbone_gw->orig);
+
+ /* send request */
+ batadv_bla_send_claim(backbone_gw->bat_priv, backbone_gw->orig,
+ backbone_gw->vid, BATADV_CLAIM_TYPE_REQUEST);
+
+ /* no local broadcasts should be sent or received, for now. */
+ if (!atomic_read(&backbone_gw->request_sent)) {
+ atomic_inc(&backbone_gw->bat_priv->bla.num_requests);
+ atomic_set(&backbone_gw->request_sent, 1);
+ }
+}
+
+/**
+ * batadv_bla_send_announce() - Send an announcement frame
+ * @bat_priv: the bat priv with all the soft interface information
+ * @backbone_gw: our backbone gateway which should be announced
+ */
+static void batadv_bla_send_announce(struct batadv_priv *bat_priv,
+ struct batadv_bla_backbone_gw *backbone_gw)
+{
+ u8 mac[ETH_ALEN];
+ __be16 crc;
+
+ memcpy(mac, batadv_announce_mac, 4);
+ spin_lock_bh(&backbone_gw->crc_lock);
+ crc = htons(backbone_gw->crc);
+ spin_unlock_bh(&backbone_gw->crc_lock);
+ memcpy(&mac[4], &crc, 2);
+
+ batadv_bla_send_claim(bat_priv, mac, backbone_gw->vid,
+ BATADV_CLAIM_TYPE_ANNOUNCE);
+}
+
+/**
+ * batadv_bla_add_claim() - Adds a claim in the claim hash
+ * @bat_priv: the bat priv with all the soft interface information
+ * @mac: the mac address of the claim
+ * @vid: the VLAN ID of the frame
+ * @backbone_gw: the backbone gateway which claims it
+ */
+static void batadv_bla_add_claim(struct batadv_priv *bat_priv,
+ const u8 *mac, const unsigned short vid,
+ struct batadv_bla_backbone_gw *backbone_gw)
+{
+ struct batadv_bla_backbone_gw *old_backbone_gw;
+ struct batadv_bla_claim *claim;
+ struct batadv_bla_claim search_claim;
+ bool remove_crc = false;
+ int hash_added;
+
+ ether_addr_copy(search_claim.addr, mac);
+ search_claim.vid = vid;
+ claim = batadv_claim_hash_find(bat_priv, &search_claim);
+
+ /* create a new claim entry if it does not exist yet. */
+ if (!claim) {
+ claim = kzalloc(sizeof(*claim), GFP_ATOMIC);
+ if (!claim)
+ return;
+
+ ether_addr_copy(claim->addr, mac);
+ spin_lock_init(&claim->backbone_lock);
+ claim->vid = vid;
+ claim->lasttime = jiffies;
+ kref_get(&backbone_gw->refcount);
+ claim->backbone_gw = backbone_gw;
+ kref_init(&claim->refcount);
+
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): adding new entry %pM, vid %d to hash ...\n",
+ __func__, mac, batadv_print_vid(vid));
+
+ kref_get(&claim->refcount);
+ hash_added = batadv_hash_add(bat_priv->bla.claim_hash,
+ batadv_compare_claim,
+ batadv_choose_claim, claim,
+ &claim->hash_entry);
+
+ if (unlikely(hash_added != 0)) {
+ /* only local changes happened. */
+ kfree(claim);
+ return;
+ }
+ } else {
+ claim->lasttime = jiffies;
+ if (claim->backbone_gw == backbone_gw)
+ /* no need to register a new backbone */
+ goto claim_free_ref;
+
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): changing ownership for %pM, vid %d to gw %pM\n",
+ __func__, mac, batadv_print_vid(vid),
+ backbone_gw->orig);
+
+ remove_crc = true;
+ }
+
+ /* replace backbone_gw atomically and adjust reference counters */
+ spin_lock_bh(&claim->backbone_lock);
+ old_backbone_gw = claim->backbone_gw;
+ kref_get(&backbone_gw->refcount);
+ claim->backbone_gw = backbone_gw;
+ spin_unlock_bh(&claim->backbone_lock);
+
+ if (remove_crc) {
+ /* remove claim address from old backbone_gw */
+ spin_lock_bh(&old_backbone_gw->crc_lock);
+ old_backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN);
+ spin_unlock_bh(&old_backbone_gw->crc_lock);
+ }
+
+ batadv_backbone_gw_put(old_backbone_gw);
+
+ /* add claim address to new backbone_gw */
+ spin_lock_bh(&backbone_gw->crc_lock);
+ backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN);
+ spin_unlock_bh(&backbone_gw->crc_lock);
+ backbone_gw->lasttime = jiffies;
+
+claim_free_ref:
+ batadv_claim_put(claim);
+}
+
+/**
+ * batadv_bla_claim_get_backbone_gw() - Get valid reference for backbone_gw of
+ * claim
+ * @claim: claim whose backbone_gw should be returned
+ *
+ * Return: valid reference to claim::backbone_gw
+ */
+static struct batadv_bla_backbone_gw *
+batadv_bla_claim_get_backbone_gw(struct batadv_bla_claim *claim)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+
+ spin_lock_bh(&claim->backbone_lock);
+ backbone_gw = claim->backbone_gw;
+ kref_get(&backbone_gw->refcount);
+ spin_unlock_bh(&claim->backbone_lock);
+
+ return backbone_gw;
+}
+
+/**
+ * batadv_bla_del_claim() - delete a claim from the claim hash
+ * @bat_priv: the bat priv with all the soft interface information
+ * @mac: mac address of the claim to be removed
+ * @vid: VLAN id for the claim to be removed
+ */
+static void batadv_bla_del_claim(struct batadv_priv *bat_priv,
+ const u8 *mac, const unsigned short vid)
+{
+ struct batadv_bla_claim search_claim, *claim;
+ struct batadv_bla_claim *claim_removed_entry;
+ struct hlist_node *claim_removed_node;
+
+ ether_addr_copy(search_claim.addr, mac);
+ search_claim.vid = vid;
+ claim = batadv_claim_hash_find(bat_priv, &search_claim);
+ if (!claim)
+ return;
+
+ batadv_dbg(BATADV_DBG_BLA, bat_priv, "%s(): %pM, vid %d\n", __func__,
+ mac, batadv_print_vid(vid));
+
+ claim_removed_node = batadv_hash_remove(bat_priv->bla.claim_hash,
+ batadv_compare_claim,
+ batadv_choose_claim, claim);
+ if (!claim_removed_node)
+ goto free_claim;
+
+ /* reference from the hash is gone */
+ claim_removed_entry = hlist_entry(claim_removed_node,
+ struct batadv_bla_claim, hash_entry);
+ batadv_claim_put(claim_removed_entry);
+
+free_claim:
+ /* don't need the reference from hash_find() anymore */
+ batadv_claim_put(claim);
+}
+
+/**
+ * batadv_handle_announce() - check for ANNOUNCE frame
+ * @bat_priv: the bat priv with all the soft interface information
+ * @an_addr: announcement mac address (ARP Sender HW address)
+ * @backbone_addr: originator address of the sender (Ethernet source MAC)
+ * @vid: the VLAN ID of the frame
+ *
+ * Return: true if handled
+ */
+static bool batadv_handle_announce(struct batadv_priv *bat_priv, u8 *an_addr,
+ u8 *backbone_addr, unsigned short vid)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+ u16 backbone_crc, crc;
+
+ if (memcmp(an_addr, batadv_announce_mac, 4) != 0)
+ return false;
+
+ backbone_gw = batadv_bla_get_backbone_gw(bat_priv, backbone_addr, vid,
+ false);
+
+ if (unlikely(!backbone_gw))
+ return true;
+
+ /* handle as ANNOUNCE frame */
+ backbone_gw->lasttime = jiffies;
+ crc = ntohs(*((__force __be16 *)(&an_addr[4])));
+
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): ANNOUNCE vid %d (sent by %pM)... CRC = %#.4x\n",
+ __func__, batadv_print_vid(vid), backbone_gw->orig, crc);
+
+ spin_lock_bh(&backbone_gw->crc_lock);
+ backbone_crc = backbone_gw->crc;
+ spin_unlock_bh(&backbone_gw->crc_lock);
+
+ if (backbone_crc != crc) {
+ batadv_dbg(BATADV_DBG_BLA, backbone_gw->bat_priv,
+ "%s(): CRC FAILED for %pM/%d (my = %#.4x, sent = %#.4x)\n",
+ __func__, backbone_gw->orig,
+ batadv_print_vid(backbone_gw->vid),
+ backbone_crc, crc);
+
+ batadv_bla_send_request(backbone_gw);
+ } else {
+ /* if we have sent a request and the crc was OK,
+ * we can allow traffic again.
+ */
+ if (atomic_read(&backbone_gw->request_sent)) {
+ atomic_dec(&backbone_gw->bat_priv->bla.num_requests);
+ atomic_set(&backbone_gw->request_sent, 0);
+ }
+ }
+
+ batadv_backbone_gw_put(backbone_gw);
+ return true;
+}
+
+/**
+ * batadv_handle_request() - check for REQUEST frame
+ * @bat_priv: the bat priv with all the soft interface information
+ * @primary_if: the primary hard interface of this batman soft interface
+ * @backbone_addr: backbone address to be requested (ARP sender HW MAC)
+ * @ethhdr: ethernet header of a packet
+ * @vid: the VLAN ID of the frame
+ *
+ * Return: true if handled
+ */
+static bool batadv_handle_request(struct batadv_priv *bat_priv,
+ struct batadv_hard_iface *primary_if,
+ u8 *backbone_addr, struct ethhdr *ethhdr,
+ unsigned short vid)
+{
+ /* check for REQUEST frame */
+ if (!batadv_compare_eth(backbone_addr, ethhdr->h_dest))
+ return false;
+
+ /* sanity check, this should not happen on a normal switch,
+ * we ignore it in this case.
+ */
+ if (!batadv_compare_eth(ethhdr->h_dest, primary_if->net_dev->dev_addr))
+ return true;
+
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): REQUEST vid %d (sent by %pM)...\n",
+ __func__, batadv_print_vid(vid), ethhdr->h_source);
+
+ batadv_bla_answer_request(bat_priv, primary_if, vid);
+ return true;
+}
+
+/**
+ * batadv_handle_unclaim() - check for UNCLAIM frame
+ * @bat_priv: the bat priv with all the soft interface information
+ * @primary_if: the primary hard interface of this batman soft interface
+ * @backbone_addr: originator address of the backbone (Ethernet source)
+ * @claim_addr: Client to be unclaimed (ARP sender HW MAC)
+ * @vid: the VLAN ID of the frame
+ *
+ * Return: true if handled
+ */
+static bool batadv_handle_unclaim(struct batadv_priv *bat_priv,
+ struct batadv_hard_iface *primary_if,
+ const u8 *backbone_addr, const u8 *claim_addr,
+ unsigned short vid)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+
+ /* unclaim in any case if it is our own */
+ if (primary_if && batadv_compare_eth(backbone_addr,
+ primary_if->net_dev->dev_addr))
+ batadv_bla_send_claim(bat_priv, claim_addr, vid,
+ BATADV_CLAIM_TYPE_UNCLAIM);
+
+ backbone_gw = batadv_backbone_hash_find(bat_priv, backbone_addr, vid);
+
+ if (!backbone_gw)
+ return true;
+
+ /* this must be an UNCLAIM frame */
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): UNCLAIM %pM on vid %d (sent by %pM)...\n", __func__,
+ claim_addr, batadv_print_vid(vid), backbone_gw->orig);
+
+ batadv_bla_del_claim(bat_priv, claim_addr, vid);
+ batadv_backbone_gw_put(backbone_gw);
+ return true;
+}
+
+/**
+ * batadv_handle_claim() - check for CLAIM frame
+ * @bat_priv: the bat priv with all the soft interface information
+ * @primary_if: the primary hard interface of this batman soft interface
+ * @backbone_addr: originator address of the backbone (Ethernet Source)
+ * @claim_addr: client mac address to be claimed (ARP sender HW MAC)
+ * @vid: the VLAN ID of the frame
+ *
+ * Return: true if handled
+ */
+static bool batadv_handle_claim(struct batadv_priv *bat_priv,
+ struct batadv_hard_iface *primary_if,
+ const u8 *backbone_addr, const u8 *claim_addr,
+ unsigned short vid)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+
+ /* register the gateway if not yet available, and add the claim. */
+
+ backbone_gw = batadv_bla_get_backbone_gw(bat_priv, backbone_addr, vid,
+ false);
+
+ if (unlikely(!backbone_gw))
+ return true;
+
+ /* this must be a CLAIM frame */
+ batadv_bla_add_claim(bat_priv, claim_addr, vid, backbone_gw);
+ if (batadv_compare_eth(backbone_addr, primary_if->net_dev->dev_addr))
+ batadv_bla_send_claim(bat_priv, claim_addr, vid,
+ BATADV_CLAIM_TYPE_CLAIM);
+
+ /* TODO: we could call something like tt_local_del() here. */
+
+ batadv_backbone_gw_put(backbone_gw);
+ return true;
+}
+
+/**
+ * batadv_check_claim_group() - check for claim group membership
+ * @bat_priv: the bat priv with all the soft interface information
+ * @primary_if: the primary interface of this batman interface
+ * @hw_src: the Hardware source in the ARP Header
+ * @hw_dst: the Hardware destination in the ARP Header
+ * @ethhdr: pointer to the Ethernet header of the claim frame
+ *
+ * checks if it is a claim packet and if it's on the same group.
+ * This function also applies the group ID of the sender
+ * if it is in the same mesh.
+ *
+ * Return:
+ * 2 - if it is a claim packet and on the same group
+ * 1 - if is a claim packet from another group
+ * 0 - if it is not a claim packet
+ */
+static int batadv_check_claim_group(struct batadv_priv *bat_priv,
+ struct batadv_hard_iface *primary_if,
+ u8 *hw_src, u8 *hw_dst,
+ struct ethhdr *ethhdr)
+{
+ u8 *backbone_addr;
+ struct batadv_orig_node *orig_node;
+ struct batadv_bla_claim_dst *bla_dst, *bla_dst_own;
+
+ bla_dst = (struct batadv_bla_claim_dst *)hw_dst;
+ bla_dst_own = &bat_priv->bla.claim_dest;
+
+ /* if announcement packet, use the source,
+ * otherwise assume it is in the hw_src
+ */
+ switch (bla_dst->type) {
+ case BATADV_CLAIM_TYPE_CLAIM:
+ backbone_addr = hw_src;
+ break;
+ case BATADV_CLAIM_TYPE_REQUEST:
+ case BATADV_CLAIM_TYPE_ANNOUNCE:
+ case BATADV_CLAIM_TYPE_UNCLAIM:
+ backbone_addr = ethhdr->h_source;
+ break;
+ default:
+ return 0;
+ }
+
+ /* don't accept claim frames from ourselves */
+ if (batadv_compare_eth(backbone_addr, primary_if->net_dev->dev_addr))
+ return 0;
+
+ /* if its already the same group, it is fine. */
+ if (bla_dst->group == bla_dst_own->group)
+ return 2;
+
+ /* lets see if this originator is in our mesh */
+ orig_node = batadv_orig_hash_find(bat_priv, backbone_addr);
+
+ /* don't accept claims from gateways which are not in
+ * the same mesh or group.
+ */
+ if (!orig_node)
+ return 1;
+
+ /* if our mesh friends mac is bigger, use it for ourselves. */
+ if (ntohs(bla_dst->group) > ntohs(bla_dst_own->group)) {
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "taking other backbones claim group: %#.4x\n",
+ ntohs(bla_dst->group));
+ bla_dst_own->group = bla_dst->group;
+ }
+
+ batadv_orig_node_put(orig_node);
+
+ return 2;
+}
+
+/**
+ * batadv_bla_process_claim() - Check if this is a claim frame, and process it
+ * @bat_priv: the bat priv with all the soft interface information
+ * @primary_if: the primary hard interface of this batman soft interface
+ * @skb: the frame to be checked
+ *
+ * Return: true if it was a claim frame, otherwise return false to
+ * tell the callee that it can use the frame on its own.
+ */
+static bool batadv_bla_process_claim(struct batadv_priv *bat_priv,
+ struct batadv_hard_iface *primary_if,
+ struct sk_buff *skb)
+{
+ struct batadv_bla_claim_dst *bla_dst, *bla_dst_own;
+ u8 *hw_src, *hw_dst;
+ struct vlan_hdr *vhdr, vhdr_buf;
+ struct ethhdr *ethhdr;
+ struct arphdr *arphdr;
+ unsigned short vid;
+ int vlan_depth = 0;
+ __be16 proto;
+ int headlen;
+ int ret;
+
+ vid = batadv_get_vid(skb, 0);
+ ethhdr = eth_hdr(skb);
+
+ proto = ethhdr->h_proto;
+ headlen = ETH_HLEN;
+ if (vid & BATADV_VLAN_HAS_TAG) {
+ /* Traverse the VLAN/Ethertypes.
+ *
+ * At this point it is known that the first protocol is a VLAN
+ * header, so start checking at the encapsulated protocol.
+ *
+ * The depth of the VLAN headers is recorded to drop BLA claim
+ * frames encapsulated into multiple VLAN headers (QinQ).
+ */
+ do {
+ vhdr = skb_header_pointer(skb, headlen, VLAN_HLEN,
+ &vhdr_buf);
+ if (!vhdr)
+ return false;
+
+ proto = vhdr->h_vlan_encapsulated_proto;
+ headlen += VLAN_HLEN;
+ vlan_depth++;
+ } while (proto == htons(ETH_P_8021Q));
+ }
+
+ if (proto != htons(ETH_P_ARP))
+ return false; /* not a claim frame */
+
+ /* this must be a ARP frame. check if it is a claim. */
+
+ if (unlikely(!pskb_may_pull(skb, headlen + arp_hdr_len(skb->dev))))
+ return false;
+
+ /* pskb_may_pull() may have modified the pointers, get ethhdr again */
+ ethhdr = eth_hdr(skb);
+ arphdr = (struct arphdr *)((u8 *)ethhdr + headlen);
+
+ /* Check whether the ARP frame carries a valid
+ * IP information
+ */
+ if (arphdr->ar_hrd != htons(ARPHRD_ETHER))
+ return false;
+ if (arphdr->ar_pro != htons(ETH_P_IP))
+ return false;
+ if (arphdr->ar_hln != ETH_ALEN)
+ return false;
+ if (arphdr->ar_pln != 4)
+ return false;
+
+ hw_src = (u8 *)arphdr + sizeof(struct arphdr);
+ hw_dst = hw_src + ETH_ALEN + 4;
+ bla_dst = (struct batadv_bla_claim_dst *)hw_dst;
+ bla_dst_own = &bat_priv->bla.claim_dest;
+
+ /* check if it is a claim frame in general */
+ if (memcmp(bla_dst->magic, bla_dst_own->magic,
+ sizeof(bla_dst->magic)) != 0)
+ return false;
+
+ /* check if there is a claim frame encapsulated deeper in (QinQ) and
+ * drop that, as this is not supported by BLA but should also not be
+ * sent via the mesh.
+ */
+ if (vlan_depth > 1)
+ return true;
+
+ /* Let the loopdetect frames on the mesh in any case. */
+ if (bla_dst->type == BATADV_CLAIM_TYPE_LOOPDETECT)
+ return false;
+
+ /* check if it is a claim frame. */
+ ret = batadv_check_claim_group(bat_priv, primary_if, hw_src, hw_dst,
+ ethhdr);
+ if (ret == 1)
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): received a claim frame from another group. From: %pM on vid %d ...(hw_src %pM, hw_dst %pM)\n",
+ __func__, ethhdr->h_source, batadv_print_vid(vid),
+ hw_src, hw_dst);
+
+ if (ret < 2)
+ return !!ret;
+
+ /* become a backbone gw ourselves on this vlan if not happened yet */
+ batadv_bla_update_own_backbone_gw(bat_priv, primary_if, vid);
+
+ /* check for the different types of claim frames ... */
+ switch (bla_dst->type) {
+ case BATADV_CLAIM_TYPE_CLAIM:
+ if (batadv_handle_claim(bat_priv, primary_if, hw_src,
+ ethhdr->h_source, vid))
+ return true;
+ break;
+ case BATADV_CLAIM_TYPE_UNCLAIM:
+ if (batadv_handle_unclaim(bat_priv, primary_if,
+ ethhdr->h_source, hw_src, vid))
+ return true;
+ break;
+
+ case BATADV_CLAIM_TYPE_ANNOUNCE:
+ if (batadv_handle_announce(bat_priv, hw_src, ethhdr->h_source,
+ vid))
+ return true;
+ break;
+ case BATADV_CLAIM_TYPE_REQUEST:
+ if (batadv_handle_request(bat_priv, primary_if, hw_src, ethhdr,
+ vid))
+ return true;
+ break;
+ }
+
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): ERROR - this looks like a claim frame, but is useless. eth src %pM on vid %d ...(hw_src %pM, hw_dst %pM)\n",
+ __func__, ethhdr->h_source, batadv_print_vid(vid), hw_src,
+ hw_dst);
+ return true;
+}
+
+/**
+ * batadv_bla_purge_backbone_gw() - Remove backbone gateways after a timeout or
+ * immediately
+ * @bat_priv: the bat priv with all the soft interface information
+ * @now: whether the whole hash shall be wiped now
+ *
+ * Check when we last heard from other nodes, and remove them in case of
+ * a time out, or clean all backbone gws if now is set.
+ */
+static void batadv_bla_purge_backbone_gw(struct batadv_priv *bat_priv, int now)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+ struct hlist_node *node_tmp;
+ struct hlist_head *head;
+ struct batadv_hashtable *hash;
+ spinlock_t *list_lock; /* protects write access to the hash lists */
+ int i;
+
+ hash = bat_priv->bla.backbone_hash;
+ if (!hash)
+ return;
+
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+ list_lock = &hash->list_locks[i];
+
+ spin_lock_bh(list_lock);
+ hlist_for_each_entry_safe(backbone_gw, node_tmp,
+ head, hash_entry) {
+ if (now)
+ goto purge_now;
+ if (!batadv_has_timed_out(backbone_gw->lasttime,
+ BATADV_BLA_BACKBONE_TIMEOUT))
+ continue;
+
+ batadv_dbg(BATADV_DBG_BLA, backbone_gw->bat_priv,
+ "%s(): backbone gw %pM timed out\n",
+ __func__, backbone_gw->orig);
+
+purge_now:
+ /* don't wait for the pending request anymore */
+ if (atomic_read(&backbone_gw->request_sent))
+ atomic_dec(&bat_priv->bla.num_requests);
+
+ batadv_bla_del_backbone_claims(backbone_gw);
+
+ hlist_del_rcu(&backbone_gw->hash_entry);
+ batadv_backbone_gw_put(backbone_gw);
+ }
+ spin_unlock_bh(list_lock);
+ }
+}
+
+/**
+ * batadv_bla_purge_claims() - Remove claims after a timeout or immediately
+ * @bat_priv: the bat priv with all the soft interface information
+ * @primary_if: the selected primary interface, may be NULL if now is set
+ * @now: whether the whole hash shall be wiped now
+ *
+ * Check when we heard last time from our own claims, and remove them in case of
+ * a time out, or clean all claims if now is set
+ */
+static void batadv_bla_purge_claims(struct batadv_priv *bat_priv,
+ struct batadv_hard_iface *primary_if,
+ int now)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+ struct batadv_bla_claim *claim;
+ struct hlist_head *head;
+ struct batadv_hashtable *hash;
+ int i;
+
+ hash = bat_priv->bla.claim_hash;
+ if (!hash)
+ return;
+
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(claim, head, hash_entry) {
+ backbone_gw = batadv_bla_claim_get_backbone_gw(claim);
+ if (now)
+ goto purge_now;
+
+ if (!batadv_compare_eth(backbone_gw->orig,
+ primary_if->net_dev->dev_addr))
+ goto skip;
+
+ if (!batadv_has_timed_out(claim->lasttime,
+ BATADV_BLA_CLAIM_TIMEOUT))
+ goto skip;
+
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): timed out.\n", __func__);
+
+purge_now:
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): %pM, vid %d\n", __func__,
+ claim->addr, claim->vid);
+
+ batadv_handle_unclaim(bat_priv, primary_if,
+ backbone_gw->orig,
+ claim->addr, claim->vid);
+skip:
+ batadv_backbone_gw_put(backbone_gw);
+ }
+ rcu_read_unlock();
+ }
+}
+
+/**
+ * batadv_bla_update_orig_address() - Update the backbone gateways when the own
+ * originator address changes
+ * @bat_priv: the bat priv with all the soft interface information
+ * @primary_if: the new selected primary_if
+ * @oldif: the old primary interface, may be NULL
+ */
+void batadv_bla_update_orig_address(struct batadv_priv *bat_priv,
+ struct batadv_hard_iface *primary_if,
+ struct batadv_hard_iface *oldif)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+ struct hlist_head *head;
+ struct batadv_hashtable *hash;
+ __be16 group;
+ int i;
+
+ /* reset bridge loop avoidance group id */
+ group = htons(crc16(0, primary_if->net_dev->dev_addr, ETH_ALEN));
+ bat_priv->bla.claim_dest.group = group;
+
+ /* purge everything when bridge loop avoidance is turned off */
+ if (!atomic_read(&bat_priv->bridge_loop_avoidance))
+ oldif = NULL;
+
+ if (!oldif) {
+ batadv_bla_purge_claims(bat_priv, NULL, 1);
+ batadv_bla_purge_backbone_gw(bat_priv, 1);
+ return;
+ }
+
+ hash = bat_priv->bla.backbone_hash;
+ if (!hash)
+ return;
+
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(backbone_gw, head, hash_entry) {
+ /* own orig still holds the old value. */
+ if (!batadv_compare_eth(backbone_gw->orig,
+ oldif->net_dev->dev_addr))
+ continue;
+
+ ether_addr_copy(backbone_gw->orig,
+ primary_if->net_dev->dev_addr);
+ /* send an announce frame so others will ask for our
+ * claims and update their tables.
+ */
+ batadv_bla_send_announce(bat_priv, backbone_gw);
+ }
+ rcu_read_unlock();
+ }
+}
+
+/**
+ * batadv_bla_send_loopdetect() - send a loopdetect frame
+ * @bat_priv: the bat priv with all the soft interface information
+ * @backbone_gw: the backbone gateway for which a loop should be detected
+ *
+ * To detect loops that the bridge loop avoidance can't handle, send a loop
+ * detection packet on the backbone. Unlike other BLA frames, this frame will
+ * be allowed on the mesh by other nodes. If it is received on the mesh, this
+ * indicates that there is a loop.
+ */
+static void
+batadv_bla_send_loopdetect(struct batadv_priv *bat_priv,
+ struct batadv_bla_backbone_gw *backbone_gw)
+{
+ batadv_dbg(BATADV_DBG_BLA, bat_priv, "Send loopdetect frame for vid %d\n",
+ backbone_gw->vid);
+ batadv_bla_send_claim(bat_priv, bat_priv->bla.loopdetect_addr,
+ backbone_gw->vid, BATADV_CLAIM_TYPE_LOOPDETECT);
+}
+
+/**
+ * batadv_bla_status_update() - purge bla interfaces if necessary
+ * @net_dev: the soft interface net device
+ */
+void batadv_bla_status_update(struct net_device *net_dev)
+{
+ 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)
+ return;
+
+ /* this function already purges everything when bla is disabled,
+ * so just call that one.
+ */
+ batadv_bla_update_orig_address(bat_priv, primary_if, primary_if);
+ batadv_hardif_put(primary_if);
+}
+
+/**
+ * batadv_bla_periodic_work() - performs periodic bla work
+ * @work: kernel work struct
+ *
+ * periodic work to do:
+ * * purge structures when they are too old
+ * * send announcements
+ */
+static void batadv_bla_periodic_work(struct work_struct *work)
+{
+ struct delayed_work *delayed_work;
+ struct batadv_priv *bat_priv;
+ struct batadv_priv_bla *priv_bla;
+ struct hlist_head *head;
+ struct batadv_bla_backbone_gw *backbone_gw;
+ struct batadv_hashtable *hash;
+ struct batadv_hard_iface *primary_if;
+ bool send_loopdetect = false;
+ int i;
+
+ delayed_work = to_delayed_work(work);
+ priv_bla = container_of(delayed_work, struct batadv_priv_bla, work);
+ bat_priv = container_of(priv_bla, struct batadv_priv, bla);
+ primary_if = batadv_primary_if_get_selected(bat_priv);
+ if (!primary_if)
+ goto out;
+
+ batadv_bla_purge_claims(bat_priv, primary_if, 0);
+ batadv_bla_purge_backbone_gw(bat_priv, 0);
+
+ if (!atomic_read(&bat_priv->bridge_loop_avoidance))
+ goto out;
+
+ if (atomic_dec_and_test(&bat_priv->bla.loopdetect_next)) {
+ /* set a new random mac address for the next bridge loop
+ * detection frames. Set the locally administered bit to avoid
+ * collisions with users mac addresses.
+ */
+ eth_random_addr(bat_priv->bla.loopdetect_addr);
+ bat_priv->bla.loopdetect_addr[0] = 0xba;
+ bat_priv->bla.loopdetect_addr[1] = 0xbe;
+ bat_priv->bla.loopdetect_lasttime = jiffies;
+ atomic_set(&bat_priv->bla.loopdetect_next,
+ BATADV_BLA_LOOPDETECT_PERIODS);
+
+ /* mark for sending loop detect on all VLANs */
+ send_loopdetect = true;
+ }
+
+ hash = bat_priv->bla.backbone_hash;
+ if (!hash)
+ goto out;
+
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(backbone_gw, head, hash_entry) {
+ if (!batadv_compare_eth(backbone_gw->orig,
+ primary_if->net_dev->dev_addr))
+ continue;
+
+ backbone_gw->lasttime = jiffies;
+
+ batadv_bla_send_announce(bat_priv, backbone_gw);
+ if (send_loopdetect)
+ batadv_bla_send_loopdetect(bat_priv,
+ backbone_gw);
+
+ /* request_sent is only set after creation to avoid
+ * problems when we are not yet known as backbone gw
+ * in the backbone.
+ *
+ * We can reset this now after we waited some periods
+ * to give bridge forward delays and bla group forming
+ * some grace time.
+ */
+
+ if (atomic_read(&backbone_gw->request_sent) == 0)
+ continue;
+
+ if (!atomic_dec_and_test(&backbone_gw->wait_periods))
+ continue;
+
+ atomic_dec(&backbone_gw->bat_priv->bla.num_requests);
+ atomic_set(&backbone_gw->request_sent, 0);
+ }
+ rcu_read_unlock();
+ }
+out:
+ batadv_hardif_put(primary_if);
+
+ queue_delayed_work(batadv_event_workqueue, &bat_priv->bla.work,
+ msecs_to_jiffies(BATADV_BLA_PERIOD_LENGTH));
+}
+
+/* The hash for claim and backbone hash receive the same key because they
+ * are getting initialized by hash_new with the same key. Reinitializing
+ * them with to different keys to allow nested locking without generating
+ * lockdep warnings
+ */
+static struct lock_class_key batadv_claim_hash_lock_class_key;
+static struct lock_class_key batadv_backbone_hash_lock_class_key;
+
+/**
+ * batadv_bla_init() - initialize all bla structures
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Return: 0 on success, < 0 on error.
+ */
+int batadv_bla_init(struct batadv_priv *bat_priv)
+{
+ int i;
+ u8 claim_dest[ETH_ALEN] = {0xff, 0x43, 0x05, 0x00, 0x00, 0x00};
+ struct batadv_hard_iface *primary_if;
+ u16 crc;
+ unsigned long entrytime;
+
+ spin_lock_init(&bat_priv->bla.bcast_duplist_lock);
+
+ batadv_dbg(BATADV_DBG_BLA, bat_priv, "bla hash registering\n");
+
+ /* setting claim destination address */
+ memcpy(&bat_priv->bla.claim_dest.magic, claim_dest, 3);
+ bat_priv->bla.claim_dest.type = 0;
+ primary_if = batadv_primary_if_get_selected(bat_priv);
+ if (primary_if) {
+ crc = crc16(0, primary_if->net_dev->dev_addr, ETH_ALEN);
+ bat_priv->bla.claim_dest.group = htons(crc);
+ batadv_hardif_put(primary_if);
+ } else {
+ bat_priv->bla.claim_dest.group = 0; /* will be set later */
+ }
+
+ /* initialize the duplicate list */
+ entrytime = jiffies - msecs_to_jiffies(BATADV_DUPLIST_TIMEOUT);
+ for (i = 0; i < BATADV_DUPLIST_SIZE; i++)
+ bat_priv->bla.bcast_duplist[i].entrytime = entrytime;
+ bat_priv->bla.bcast_duplist_curr = 0;
+
+ atomic_set(&bat_priv->bla.loopdetect_next,
+ BATADV_BLA_LOOPDETECT_PERIODS);
+
+ if (bat_priv->bla.claim_hash)
+ return 0;
+
+ bat_priv->bla.claim_hash = batadv_hash_new(128);
+ if (!bat_priv->bla.claim_hash)
+ return -ENOMEM;
+
+ bat_priv->bla.backbone_hash = batadv_hash_new(32);
+ if (!bat_priv->bla.backbone_hash) {
+ batadv_hash_destroy(bat_priv->bla.claim_hash);
+ return -ENOMEM;
+ }
+
+ batadv_hash_set_lock_class(bat_priv->bla.claim_hash,
+ &batadv_claim_hash_lock_class_key);
+ batadv_hash_set_lock_class(bat_priv->bla.backbone_hash,
+ &batadv_backbone_hash_lock_class_key);
+
+ batadv_dbg(BATADV_DBG_BLA, bat_priv, "bla hashes initialized\n");
+
+ INIT_DELAYED_WORK(&bat_priv->bla.work, batadv_bla_periodic_work);
+
+ queue_delayed_work(batadv_event_workqueue, &bat_priv->bla.work,
+ msecs_to_jiffies(BATADV_BLA_PERIOD_LENGTH));
+ return 0;
+}
+
+/**
+ * batadv_bla_check_duplist() - Check if a frame is in the broadcast dup.
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: contains the multicast packet to be checked
+ * @payload_ptr: pointer to position inside the head buffer of the skb
+ * marking the start of the data to be CRC'ed
+ * @orig: originator mac address, NULL if unknown
+ *
+ * Check if it is on our broadcast list. Another gateway might have sent the
+ * same packet because it is connected to the same backbone, so we have to
+ * remove this duplicate.
+ *
+ * This is performed by checking the CRC, which will tell us
+ * with a good chance that it is the same packet. If it is furthermore
+ * sent by another host, drop it. We allow equal packets from
+ * the same host however as this might be intended.
+ *
+ * Return: true if a packet is in the duplicate list, false otherwise.
+ */
+static bool batadv_bla_check_duplist(struct batadv_priv *bat_priv,
+ struct sk_buff *skb, u8 *payload_ptr,
+ const u8 *orig)
+{
+ struct batadv_bcast_duplist_entry *entry;
+ bool ret = false;
+ int i, curr;
+ __be32 crc;
+
+ /* calculate the crc ... */
+ crc = batadv_skb_crc32(skb, payload_ptr);
+
+ spin_lock_bh(&bat_priv->bla.bcast_duplist_lock);
+
+ for (i = 0; i < BATADV_DUPLIST_SIZE; i++) {
+ curr = (bat_priv->bla.bcast_duplist_curr + i);
+ curr %= BATADV_DUPLIST_SIZE;
+ entry = &bat_priv->bla.bcast_duplist[curr];
+
+ /* we can stop searching if the entry is too old ;
+ * later entries will be even older
+ */
+ if (batadv_has_timed_out(entry->entrytime,
+ BATADV_DUPLIST_TIMEOUT))
+ break;
+
+ if (entry->crc != crc)
+ continue;
+
+ /* are the originators both known and not anonymous? */
+ if (orig && !is_zero_ether_addr(orig) &&
+ !is_zero_ether_addr(entry->orig)) {
+ /* If known, check if the new frame came from
+ * the same originator:
+ * We are safe to take identical frames from the
+ * same orig, if known, as multiplications in
+ * the mesh are detected via the (orig, seqno) pair.
+ * So we can be a bit more liberal here and allow
+ * identical frames from the same orig which the source
+ * host might have sent multiple times on purpose.
+ */
+ if (batadv_compare_eth(entry->orig, orig))
+ continue;
+ }
+
+ /* this entry seems to match: same crc, not too old,
+ * and from another gw. therefore return true to forbid it.
+ */
+ ret = true;
+ goto out;
+ }
+ /* not found, add a new entry (overwrite the oldest entry)
+ * and allow it, its the first occurrence.
+ */
+ curr = (bat_priv->bla.bcast_duplist_curr + BATADV_DUPLIST_SIZE - 1);
+ curr %= BATADV_DUPLIST_SIZE;
+ entry = &bat_priv->bla.bcast_duplist[curr];
+ entry->crc = crc;
+ entry->entrytime = jiffies;
+
+ /* known originator */
+ if (orig)
+ ether_addr_copy(entry->orig, orig);
+ /* anonymous originator */
+ else
+ eth_zero_addr(entry->orig);
+
+ bat_priv->bla.bcast_duplist_curr = curr;
+
+out:
+ spin_unlock_bh(&bat_priv->bla.bcast_duplist_lock);
+
+ return ret;
+}
+
+/**
+ * batadv_bla_check_ucast_duplist() - Check if a frame is in the broadcast dup.
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: contains the multicast packet to be checked, decapsulated from a
+ * unicast_packet
+ *
+ * Check if it is on our broadcast list. Another gateway might have sent the
+ * same packet because it is connected to the same backbone, so we have to
+ * remove this duplicate.
+ *
+ * Return: true if a packet is in the duplicate list, false otherwise.
+ */
+static bool batadv_bla_check_ucast_duplist(struct batadv_priv *bat_priv,
+ struct sk_buff *skb)
+{
+ return batadv_bla_check_duplist(bat_priv, skb, (u8 *)skb->data, NULL);
+}
+
+/**
+ * batadv_bla_check_bcast_duplist() - Check if a frame is in the broadcast dup.
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: contains the bcast_packet to be checked
+ *
+ * Check if it is on our broadcast list. Another gateway might have sent the
+ * same packet because it is connected to the same backbone, so we have to
+ * remove this duplicate.
+ *
+ * Return: true if a packet is in the duplicate list, false otherwise.
+ */
+bool batadv_bla_check_bcast_duplist(struct batadv_priv *bat_priv,
+ struct sk_buff *skb)
+{
+ struct batadv_bcast_packet *bcast_packet;
+ u8 *payload_ptr;
+
+ bcast_packet = (struct batadv_bcast_packet *)skb->data;
+ payload_ptr = (u8 *)(bcast_packet + 1);
+
+ return batadv_bla_check_duplist(bat_priv, skb, payload_ptr,
+ bcast_packet->orig);
+}
+
+/**
+ * batadv_bla_is_backbone_gw_orig() - Check if the originator is a gateway for
+ * the VLAN identified by vid.
+ * @bat_priv: the bat priv with all the soft interface information
+ * @orig: originator mac address
+ * @vid: VLAN identifier
+ *
+ * Return: true if orig is a backbone for this vid, false otherwise.
+ */
+bool batadv_bla_is_backbone_gw_orig(struct batadv_priv *bat_priv, u8 *orig,
+ unsigned short vid)
+{
+ struct batadv_hashtable *hash = bat_priv->bla.backbone_hash;
+ struct hlist_head *head;
+ struct batadv_bla_backbone_gw *backbone_gw;
+ int i;
+
+ if (!atomic_read(&bat_priv->bridge_loop_avoidance))
+ return false;
+
+ if (!hash)
+ return false;
+
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(backbone_gw, head, hash_entry) {
+ if (batadv_compare_eth(backbone_gw->orig, orig) &&
+ backbone_gw->vid == vid) {
+ rcu_read_unlock();
+ return true;
+ }
+ }
+ rcu_read_unlock();
+ }
+
+ return false;
+}
+
+/**
+ * batadv_bla_is_backbone_gw() - check if originator is a backbone gw for a VLAN
+ * @skb: the frame to be checked
+ * @orig_node: the orig_node of the frame
+ * @hdr_size: maximum length of the frame
+ *
+ * Return: true if the orig_node is also a gateway on the soft interface,
+ * otherwise it returns false.
+ */
+bool batadv_bla_is_backbone_gw(struct sk_buff *skb,
+ struct batadv_orig_node *orig_node, int hdr_size)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+ unsigned short vid;
+
+ if (!atomic_read(&orig_node->bat_priv->bridge_loop_avoidance))
+ return false;
+
+ /* first, find out the vid. */
+ if (!pskb_may_pull(skb, hdr_size + ETH_HLEN))
+ return false;
+
+ vid = batadv_get_vid(skb, hdr_size);
+
+ /* see if this originator is a backbone gw for this VLAN */
+ backbone_gw = batadv_backbone_hash_find(orig_node->bat_priv,
+ orig_node->orig, vid);
+ if (!backbone_gw)
+ return false;
+
+ batadv_backbone_gw_put(backbone_gw);
+ return true;
+}
+
+/**
+ * batadv_bla_free() - free all bla structures
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * for softinterface free or module unload
+ */
+void batadv_bla_free(struct batadv_priv *bat_priv)
+{
+ struct batadv_hard_iface *primary_if;
+
+ cancel_delayed_work_sync(&bat_priv->bla.work);
+ primary_if = batadv_primary_if_get_selected(bat_priv);
+
+ if (bat_priv->bla.claim_hash) {
+ batadv_bla_purge_claims(bat_priv, primary_if, 1);
+ batadv_hash_destroy(bat_priv->bla.claim_hash);
+ bat_priv->bla.claim_hash = NULL;
+ }
+ if (bat_priv->bla.backbone_hash) {
+ batadv_bla_purge_backbone_gw(bat_priv, 1);
+ batadv_hash_destroy(bat_priv->bla.backbone_hash);
+ bat_priv->bla.backbone_hash = NULL;
+ }
+ batadv_hardif_put(primary_if);
+}
+
+/**
+ * batadv_bla_loopdetect_check() - check and handle a detected loop
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the packet to check
+ * @primary_if: interface where the request came on
+ * @vid: the VLAN ID of the frame
+ *
+ * Checks if this packet is a loop detect frame which has been sent by us,
+ * throws an uevent and logs the event if that is the case.
+ *
+ * Return: true if it is a loop detect frame which is to be dropped, false
+ * otherwise.
+ */
+static bool
+batadv_bla_loopdetect_check(struct batadv_priv *bat_priv, struct sk_buff *skb,
+ struct batadv_hard_iface *primary_if,
+ unsigned short vid)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+ struct ethhdr *ethhdr;
+ bool ret;
+
+ ethhdr = eth_hdr(skb);
+
+ /* Only check for the MAC address and skip more checks here for
+ * performance reasons - this function is on the hotpath, after all.
+ */
+ if (!batadv_compare_eth(ethhdr->h_source,
+ bat_priv->bla.loopdetect_addr))
+ return false;
+
+ /* If the packet came too late, don't forward it on the mesh
+ * but don't consider that as loop. It might be a coincidence.
+ */
+ if (batadv_has_timed_out(bat_priv->bla.loopdetect_lasttime,
+ BATADV_BLA_LOOPDETECT_TIMEOUT))
+ return true;
+
+ backbone_gw = batadv_bla_get_backbone_gw(bat_priv,
+ primary_if->net_dev->dev_addr,
+ vid, true);
+ if (unlikely(!backbone_gw))
+ return true;
+
+ ret = queue_work(batadv_event_workqueue, &backbone_gw->report_work);
+
+ /* backbone_gw is unreferenced in the report work function
+ * if queue_work() call was successful
+ */
+ if (!ret)
+ batadv_backbone_gw_put(backbone_gw);
+
+ return true;
+}
+
+/**
+ * batadv_bla_rx() - check packets coming from the mesh.
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the frame to be checked
+ * @vid: the VLAN ID of the frame
+ * @packet_type: the batman packet type this frame came in
+ *
+ * batadv_bla_rx avoidance checks if:
+ * * we have to race for a claim
+ * * if the frame is allowed on the LAN
+ *
+ * In these cases, the skb is further handled by this function
+ *
+ * Return: true if handled, otherwise it returns false and the caller shall
+ * further process the skb.
+ */
+bool batadv_bla_rx(struct batadv_priv *bat_priv, struct sk_buff *skb,
+ unsigned short vid, int packet_type)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+ struct ethhdr *ethhdr;
+ struct batadv_bla_claim search_claim, *claim = NULL;
+ struct batadv_hard_iface *primary_if;
+ bool own_claim;
+ bool ret;
+
+ ethhdr = eth_hdr(skb);
+
+ primary_if = batadv_primary_if_get_selected(bat_priv);
+ if (!primary_if)
+ goto handled;
+
+ if (!atomic_read(&bat_priv->bridge_loop_avoidance))
+ goto allow;
+
+ if (batadv_bla_loopdetect_check(bat_priv, skb, primary_if, vid))
+ goto handled;
+
+ if (unlikely(atomic_read(&bat_priv->bla.num_requests)))
+ /* don't allow multicast packets while requests are in flight */
+ if (is_multicast_ether_addr(ethhdr->h_dest))
+ /* Both broadcast flooding or multicast-via-unicasts
+ * delivery might send to multiple backbone gateways
+ * sharing the same LAN and therefore need to coordinate
+ * which backbone gateway forwards into the LAN,
+ * by claiming the payload source address.
+ *
+ * Broadcast flooding and multicast-via-unicasts
+ * delivery use the following two batman packet types.
+ * Note: explicitly exclude BATADV_UNICAST_4ADDR,
+ * as the DHCP gateway feature will send explicitly
+ * to only one BLA gateway, so the claiming process
+ * should be avoided there.
+ */
+ if (packet_type == BATADV_BCAST ||
+ packet_type == BATADV_UNICAST)
+ goto handled;
+
+ /* potential duplicates from foreign BLA backbone gateways via
+ * multicast-in-unicast packets
+ */
+ if (is_multicast_ether_addr(ethhdr->h_dest) &&
+ packet_type == BATADV_UNICAST &&
+ batadv_bla_check_ucast_duplist(bat_priv, skb))
+ goto handled;
+
+ ether_addr_copy(search_claim.addr, ethhdr->h_source);
+ search_claim.vid = vid;
+ claim = batadv_claim_hash_find(bat_priv, &search_claim);
+
+ if (!claim) {
+ /* possible optimization: race for a claim */
+ /* No claim exists yet, claim it for us!
+ */
+
+ batadv_dbg(BATADV_DBG_BLA, bat_priv,
+ "%s(): Unclaimed MAC %pM found. Claim it. Local: %s\n",
+ __func__, ethhdr->h_source,
+ batadv_is_my_client(bat_priv,
+ ethhdr->h_source, vid) ?
+ "yes" : "no");
+ batadv_handle_claim(bat_priv, primary_if,
+ primary_if->net_dev->dev_addr,
+ ethhdr->h_source, vid);
+ goto allow;
+ }
+
+ /* if it is our own claim ... */
+ backbone_gw = batadv_bla_claim_get_backbone_gw(claim);
+ own_claim = batadv_compare_eth(backbone_gw->orig,
+ primary_if->net_dev->dev_addr);
+ batadv_backbone_gw_put(backbone_gw);
+
+ if (own_claim) {
+ /* ... allow it in any case */
+ claim->lasttime = jiffies;
+ goto allow;
+ }
+
+ /* if it is a multicast ... */
+ if (is_multicast_ether_addr(ethhdr->h_dest) &&
+ (packet_type == BATADV_BCAST || packet_type == BATADV_UNICAST)) {
+ /* ... drop it. the responsible gateway is in charge.
+ *
+ * We need to check packet type because with the gateway
+ * feature, broadcasts (like DHCP requests) may be sent
+ * using a unicast 4 address packet type. See comment above.
+ */
+ goto handled;
+ } else {
+ /* seems the client considers us as its best gateway.
+ * send a claim and update the claim table
+ * immediately.
+ */
+ batadv_handle_claim(bat_priv, primary_if,
+ primary_if->net_dev->dev_addr,
+ ethhdr->h_source, vid);
+ goto allow;
+ }
+allow:
+ batadv_bla_update_own_backbone_gw(bat_priv, primary_if, vid);
+ ret = false;
+ goto out;
+
+handled:
+ kfree_skb(skb);
+ ret = true;
+
+out:
+ batadv_hardif_put(primary_if);
+ batadv_claim_put(claim);
+ return ret;
+}
+
+/**
+ * batadv_bla_tx() - check packets going into the mesh
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the frame to be checked
+ * @vid: the VLAN ID of the frame
+ *
+ * batadv_bla_tx checks if:
+ * * a claim was received which has to be processed
+ * * the frame is allowed on the mesh
+ *
+ * in these cases, the skb is further handled by this function.
+ *
+ * This call might reallocate skb data.
+ *
+ * Return: true if handled, otherwise it returns false and the caller shall
+ * further process the skb.
+ */
+bool batadv_bla_tx(struct batadv_priv *bat_priv, struct sk_buff *skb,
+ unsigned short vid)
+{
+ struct ethhdr *ethhdr;
+ struct batadv_bla_claim search_claim, *claim = NULL;
+ struct batadv_bla_backbone_gw *backbone_gw;
+ struct batadv_hard_iface *primary_if;
+ bool client_roamed;
+ bool ret = false;
+
+ primary_if = batadv_primary_if_get_selected(bat_priv);
+ if (!primary_if)
+ goto out;
+
+ if (!atomic_read(&bat_priv->bridge_loop_avoidance))
+ goto allow;
+
+ if (batadv_bla_process_claim(bat_priv, primary_if, skb))
+ goto handled;
+
+ ethhdr = eth_hdr(skb);
+
+ if (unlikely(atomic_read(&bat_priv->bla.num_requests)))
+ /* don't allow broadcasts while requests are in flight */
+ if (is_multicast_ether_addr(ethhdr->h_dest))
+ goto handled;
+
+ ether_addr_copy(search_claim.addr, ethhdr->h_source);
+ search_claim.vid = vid;
+
+ claim = batadv_claim_hash_find(bat_priv, &search_claim);
+
+ /* if no claim exists, allow it. */
+ if (!claim)
+ goto allow;
+
+ /* check if we are responsible. */
+ backbone_gw = batadv_bla_claim_get_backbone_gw(claim);
+ client_roamed = batadv_compare_eth(backbone_gw->orig,
+ primary_if->net_dev->dev_addr);
+ batadv_backbone_gw_put(backbone_gw);
+
+ if (client_roamed) {
+ /* if yes, the client has roamed and we have
+ * to unclaim it.
+ */
+ if (batadv_has_timed_out(claim->lasttime, 100)) {
+ /* only unclaim if the last claim entry is
+ * older than 100 ms to make sure we really
+ * have a roaming client here.
+ */
+ batadv_dbg(BATADV_DBG_BLA, bat_priv, "%s(): Roaming client %pM detected. Unclaim it.\n",
+ __func__, ethhdr->h_source);
+ batadv_handle_unclaim(bat_priv, primary_if,
+ primary_if->net_dev->dev_addr,
+ ethhdr->h_source, vid);
+ goto allow;
+ } else {
+ batadv_dbg(BATADV_DBG_BLA, bat_priv, "%s(): Race for claim %pM detected. Drop packet.\n",
+ __func__, ethhdr->h_source);
+ goto handled;
+ }
+ }
+
+ /* check if it is a multicast/broadcast frame */
+ if (is_multicast_ether_addr(ethhdr->h_dest)) {
+ /* drop it. the responsible gateway has forwarded it into
+ * the backbone network.
+ */
+ goto handled;
+ } else {
+ /* we must allow it. at least if we are
+ * responsible for the DESTINATION.
+ */
+ goto allow;
+ }
+allow:
+ batadv_bla_update_own_backbone_gw(bat_priv, primary_if, vid);
+ ret = false;
+ goto out;
+handled:
+ ret = true;
+out:
+ batadv_hardif_put(primary_if);
+ batadv_claim_put(claim);
+ return ret;
+}
+
+/**
+ * batadv_bla_claim_dump_entry() - dump one entry of the claim table
+ * to a netlink socket
+ * @msg: buffer for the message
+ * @portid: netlink port
+ * @cb: Control block containing additional options
+ * @primary_if: primary interface
+ * @claim: entry to dump
+ *
+ * Return: 0 or error code.
+ */
+static int
+batadv_bla_claim_dump_entry(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
+ struct batadv_hard_iface *primary_if,
+ struct batadv_bla_claim *claim)
+{
+ const u8 *primary_addr = primary_if->net_dev->dev_addr;
+ u16 backbone_crc;
+ bool is_own;
+ void *hdr;
+ int ret = -EINVAL;
+
+ hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
+ &batadv_netlink_family, NLM_F_MULTI,
+ BATADV_CMD_GET_BLA_CLAIM);
+ if (!hdr) {
+ ret = -ENOBUFS;
+ goto out;
+ }
+
+ genl_dump_check_consistent(cb, hdr);
+
+ is_own = batadv_compare_eth(claim->backbone_gw->orig,
+ primary_addr);
+
+ spin_lock_bh(&claim->backbone_gw->crc_lock);
+ backbone_crc = claim->backbone_gw->crc;
+ spin_unlock_bh(&claim->backbone_gw->crc_lock);
+
+ if (is_own)
+ if (nla_put_flag(msg, BATADV_ATTR_BLA_OWN)) {
+ genlmsg_cancel(msg, hdr);
+ goto out;
+ }
+
+ if (nla_put(msg, BATADV_ATTR_BLA_ADDRESS, ETH_ALEN, claim->addr) ||
+ nla_put_u16(msg, BATADV_ATTR_BLA_VID, claim->vid) ||
+ nla_put(msg, BATADV_ATTR_BLA_BACKBONE, ETH_ALEN,
+ claim->backbone_gw->orig) ||
+ nla_put_u16(msg, BATADV_ATTR_BLA_CRC,
+ backbone_crc)) {
+ genlmsg_cancel(msg, hdr);
+ goto out;
+ }
+
+ genlmsg_end(msg, hdr);
+ ret = 0;
+
+out:
+ return ret;
+}
+
+/**
+ * batadv_bla_claim_dump_bucket() - dump one bucket of the claim table
+ * to a netlink socket
+ * @msg: buffer for the message
+ * @portid: netlink port
+ * @cb: Control block containing additional options
+ * @primary_if: primary interface
+ * @hash: hash to dump
+ * @bucket: bucket index to dump
+ * @idx_skip: How many entries to skip
+ *
+ * Return: always 0.
+ */
+static int
+batadv_bla_claim_dump_bucket(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
+ struct batadv_hard_iface *primary_if,
+ struct batadv_hashtable *hash, unsigned int bucket,
+ int *idx_skip)
+{
+ struct batadv_bla_claim *claim;
+ int idx = 0;
+ int ret = 0;
+
+ spin_lock_bh(&hash->list_locks[bucket]);
+ cb->seq = atomic_read(&hash->generation) << 1 | 1;
+
+ hlist_for_each_entry(claim, &hash->table[bucket], hash_entry) {
+ if (idx++ < *idx_skip)
+ continue;
+
+ ret = batadv_bla_claim_dump_entry(msg, portid, cb,
+ primary_if, claim);
+ if (ret) {
+ *idx_skip = idx - 1;
+ goto unlock;
+ }
+ }
+
+ *idx_skip = 0;
+unlock:
+ spin_unlock_bh(&hash->list_locks[bucket]);
+ return ret;
+}
+
+/**
+ * batadv_bla_claim_dump() - dump claim table to a netlink socket
+ * @msg: buffer for the message
+ * @cb: callback structure containing arguments
+ *
+ * Return: message length.
+ */
+int batadv_bla_claim_dump(struct sk_buff *msg, struct netlink_callback *cb)
+{
+ struct batadv_hard_iface *primary_if = NULL;
+ int portid = NETLINK_CB(cb->skb).portid;
+ struct net *net = sock_net(cb->skb->sk);
+ struct net_device *soft_iface;
+ struct batadv_hashtable *hash;
+ struct batadv_priv *bat_priv;
+ int bucket = cb->args[0];
+ int idx = cb->args[1];
+ int ifindex;
+ int ret = 0;
+
+ ifindex = batadv_netlink_get_ifindex(cb->nlh,
+ BATADV_ATTR_MESH_IFINDEX);
+ if (!ifindex)
+ return -EINVAL;
+
+ soft_iface = dev_get_by_index(net, ifindex);
+ if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ bat_priv = netdev_priv(soft_iface);
+ hash = bat_priv->bla.claim_hash;
+
+ primary_if = batadv_primary_if_get_selected(bat_priv);
+ if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ while (bucket < hash->size) {
+ if (batadv_bla_claim_dump_bucket(msg, portid, cb, primary_if,
+ hash, bucket, &idx))
+ break;
+ bucket++;
+ }
+
+ cb->args[0] = bucket;
+ cb->args[1] = idx;
+
+ ret = msg->len;
+
+out:
+ batadv_hardif_put(primary_if);
+
+ dev_put(soft_iface);
+
+ return ret;
+}
+
+/**
+ * batadv_bla_backbone_dump_entry() - dump one entry of the backbone table to a
+ * netlink socket
+ * @msg: buffer for the message
+ * @portid: netlink port
+ * @cb: Control block containing additional options
+ * @primary_if: primary interface
+ * @backbone_gw: entry to dump
+ *
+ * Return: 0 or error code.
+ */
+static int
+batadv_bla_backbone_dump_entry(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
+ struct batadv_hard_iface *primary_if,
+ struct batadv_bla_backbone_gw *backbone_gw)
+{
+ const u8 *primary_addr = primary_if->net_dev->dev_addr;
+ u16 backbone_crc;
+ bool is_own;
+ int msecs;
+ void *hdr;
+ int ret = -EINVAL;
+
+ hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
+ &batadv_netlink_family, NLM_F_MULTI,
+ BATADV_CMD_GET_BLA_BACKBONE);
+ if (!hdr) {
+ ret = -ENOBUFS;
+ goto out;
+ }
+
+ genl_dump_check_consistent(cb, hdr);
+
+ is_own = batadv_compare_eth(backbone_gw->orig, primary_addr);
+
+ spin_lock_bh(&backbone_gw->crc_lock);
+ backbone_crc = backbone_gw->crc;
+ spin_unlock_bh(&backbone_gw->crc_lock);
+
+ msecs = jiffies_to_msecs(jiffies - backbone_gw->lasttime);
+
+ if (is_own)
+ if (nla_put_flag(msg, BATADV_ATTR_BLA_OWN)) {
+ genlmsg_cancel(msg, hdr);
+ goto out;
+ }
+
+ if (nla_put(msg, BATADV_ATTR_BLA_BACKBONE, ETH_ALEN,
+ backbone_gw->orig) ||
+ nla_put_u16(msg, BATADV_ATTR_BLA_VID, backbone_gw->vid) ||
+ nla_put_u16(msg, BATADV_ATTR_BLA_CRC,
+ backbone_crc) ||
+ nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS, msecs)) {
+ genlmsg_cancel(msg, hdr);
+ goto out;
+ }
+
+ genlmsg_end(msg, hdr);
+ ret = 0;
+
+out:
+ return ret;
+}
+
+/**
+ * batadv_bla_backbone_dump_bucket() - dump one bucket of the backbone table to
+ * a netlink socket
+ * @msg: buffer for the message
+ * @portid: netlink port
+ * @cb: Control block containing additional options
+ * @primary_if: primary interface
+ * @hash: hash to dump
+ * @bucket: bucket index to dump
+ * @idx_skip: How many entries to skip
+ *
+ * Return: always 0.
+ */
+static int
+batadv_bla_backbone_dump_bucket(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
+ struct batadv_hard_iface *primary_if,
+ struct batadv_hashtable *hash,
+ unsigned int bucket, int *idx_skip)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+ int idx = 0;
+ int ret = 0;
+
+ spin_lock_bh(&hash->list_locks[bucket]);
+ cb->seq = atomic_read(&hash->generation) << 1 | 1;
+
+ hlist_for_each_entry(backbone_gw, &hash->table[bucket], hash_entry) {
+ if (idx++ < *idx_skip)
+ continue;
+
+ ret = batadv_bla_backbone_dump_entry(msg, portid, cb,
+ primary_if, backbone_gw);
+ if (ret) {
+ *idx_skip = idx - 1;
+ goto unlock;
+ }
+ }
+
+ *idx_skip = 0;
+unlock:
+ spin_unlock_bh(&hash->list_locks[bucket]);
+ return ret;
+}
+
+/**
+ * batadv_bla_backbone_dump() - dump backbone table to a netlink socket
+ * @msg: buffer for the message
+ * @cb: callback structure containing arguments
+ *
+ * Return: message length.
+ */
+int batadv_bla_backbone_dump(struct sk_buff *msg, struct netlink_callback *cb)
+{
+ struct batadv_hard_iface *primary_if = NULL;
+ int portid = NETLINK_CB(cb->skb).portid;
+ struct net *net = sock_net(cb->skb->sk);
+ struct net_device *soft_iface;
+ struct batadv_hashtable *hash;
+ struct batadv_priv *bat_priv;
+ int bucket = cb->args[0];
+ int idx = cb->args[1];
+ int ifindex;
+ int ret = 0;
+
+ ifindex = batadv_netlink_get_ifindex(cb->nlh,
+ BATADV_ATTR_MESH_IFINDEX);
+ if (!ifindex)
+ return -EINVAL;
+
+ soft_iface = dev_get_by_index(net, ifindex);
+ if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ bat_priv = netdev_priv(soft_iface);
+ hash = bat_priv->bla.backbone_hash;
+
+ primary_if = batadv_primary_if_get_selected(bat_priv);
+ if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ while (bucket < hash->size) {
+ if (batadv_bla_backbone_dump_bucket(msg, portid, cb, primary_if,
+ hash, bucket, &idx))
+ break;
+ bucket++;
+ }
+
+ cb->args[0] = bucket;
+ cb->args[1] = idx;
+
+ ret = msg->len;
+
+out:
+ batadv_hardif_put(primary_if);
+
+ dev_put(soft_iface);
+
+ return ret;
+}
+
+#ifdef CONFIG_BATMAN_ADV_DAT
+/**
+ * batadv_bla_check_claim() - check if address is claimed
+ *
+ * @bat_priv: the bat priv with all the soft interface information
+ * @addr: mac address of which the claim status is checked
+ * @vid: the VLAN ID
+ *
+ * addr is checked if this address is claimed by the local device itself.
+ *
+ * Return: true if bla is disabled or the mac is claimed by the device,
+ * false if the device addr is already claimed by another gateway
+ */
+bool batadv_bla_check_claim(struct batadv_priv *bat_priv,
+ u8 *addr, unsigned short vid)
+{
+ struct batadv_bla_claim search_claim;
+ struct batadv_bla_claim *claim = NULL;
+ struct batadv_hard_iface *primary_if = NULL;
+ bool ret = true;
+
+ if (!atomic_read(&bat_priv->bridge_loop_avoidance))
+ return ret;
+
+ primary_if = batadv_primary_if_get_selected(bat_priv);
+ if (!primary_if)
+ return ret;
+
+ /* First look if the mac address is claimed */
+ ether_addr_copy(search_claim.addr, addr);
+ search_claim.vid = vid;
+
+ claim = batadv_claim_hash_find(bat_priv, &search_claim);
+
+ /* If there is a claim and we are not owner of the claim,
+ * return false.
+ */
+ if (claim) {
+ if (!batadv_compare_eth(claim->backbone_gw->orig,
+ primary_if->net_dev->dev_addr))
+ ret = false;
+ batadv_claim_put(claim);
+ }
+
+ batadv_hardif_put(primary_if);
+ return ret;
+}
+#endif