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- // SPDX-License-Identifier: GPL-2.0
- /* Copyright (C) 2011-2020 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/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/preempt.h>
- #include <linux/rculist.h>
- #include <linux/rcupdate.h>
- #include <linux/seq_file.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)
- {
- struct batadv_bla_claim *claim = (struct batadv_bla_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 = (struct batadv_bla_backbone_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, 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, 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 containg 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);
- if (in_interrupt())
- netif_rx(skb);
- else
- netif_rx_ni(skb);
- out:
- if (primary_if)
- 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, 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,
- u8 *backbone_addr, 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,
- u8 *backbone_addr, 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);
- /* dont 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:
- if (primary_if)
- 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;
- }
- if (primary_if)
- 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:
- if (primary_if)
- batadv_hardif_put(primary_if);
- if (claim)
- 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:
- if (primary_if)
- batadv_hardif_put(primary_if);
- if (claim)
- batadv_claim_put(claim);
- return ret;
- }
- #ifdef CONFIG_BATMAN_ADV_DEBUGFS
- /**
- * batadv_bla_claim_table_seq_print_text() - print the claim table in a seq file
- * @seq: seq file to print on
- * @offset: not used
- *
- * Return: always 0
- */
- int batadv_bla_claim_table_seq_print_text(struct seq_file *seq, void *offset)
- {
- struct net_device *net_dev = (struct net_device *)seq->private;
- struct batadv_priv *bat_priv = netdev_priv(net_dev);
- struct batadv_hashtable *hash = bat_priv->bla.claim_hash;
- struct batadv_bla_backbone_gw *backbone_gw;
- struct batadv_bla_claim *claim;
- struct batadv_hard_iface *primary_if;
- struct hlist_head *head;
- u16 backbone_crc;
- u32 i;
- bool is_own;
- u8 *primary_addr;
- primary_if = batadv_seq_print_text_primary_if_get(seq);
- if (!primary_if)
- goto out;
- primary_addr = primary_if->net_dev->dev_addr;
- seq_printf(seq,
- "Claims announced for the mesh %s (orig %pM, group id %#.4x)\n",
- net_dev->name, primary_addr,
- ntohs(bat_priv->bla.claim_dest.group));
- seq_puts(seq,
- " Client VID Originator [o] (CRC )\n");
- 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);
- 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);
- seq_printf(seq, " * %pM on %5d by %pM [%c] (%#.4x)\n",
- claim->addr, batadv_print_vid(claim->vid),
- backbone_gw->orig,
- (is_own ? 'x' : ' '),
- backbone_crc);
- batadv_backbone_gw_put(backbone_gw);
- }
- rcu_read_unlock();
- }
- out:
- if (primary_if)
- batadv_hardif_put(primary_if);
- return 0;
- }
- #endif
- /**
- * 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)
- {
- 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:
- if (primary_if)
- batadv_hardif_put(primary_if);
- if (soft_iface)
- dev_put(soft_iface);
- return ret;
- }
- #ifdef CONFIG_BATMAN_ADV_DEBUGFS
- /**
- * batadv_bla_backbone_table_seq_print_text() - print the backbone table in a
- * seq file
- * @seq: seq file to print on
- * @offset: not used
- *
- * Return: always 0
- */
- int batadv_bla_backbone_table_seq_print_text(struct seq_file *seq, void *offset)
- {
- struct net_device *net_dev = (struct net_device *)seq->private;
- struct batadv_priv *bat_priv = netdev_priv(net_dev);
- struct batadv_hashtable *hash = bat_priv->bla.backbone_hash;
- struct batadv_bla_backbone_gw *backbone_gw;
- struct batadv_hard_iface *primary_if;
- struct hlist_head *head;
- int secs, msecs;
- u16 backbone_crc;
- u32 i;
- bool is_own;
- u8 *primary_addr;
- primary_if = batadv_seq_print_text_primary_if_get(seq);
- if (!primary_if)
- goto out;
- primary_addr = primary_if->net_dev->dev_addr;
- seq_printf(seq,
- "Backbones announced for the mesh %s (orig %pM, group id %#.4x)\n",
- net_dev->name, primary_addr,
- ntohs(bat_priv->bla.claim_dest.group));
- seq_puts(seq, " Originator VID last seen (CRC )\n");
- for (i = 0; i < hash->size; i++) {
- head = &hash->table[i];
- rcu_read_lock();
- hlist_for_each_entry_rcu(backbone_gw, head, hash_entry) {
- msecs = jiffies_to_msecs(jiffies -
- backbone_gw->lasttime);
- secs = msecs / 1000;
- msecs = msecs % 1000;
- is_own = batadv_compare_eth(backbone_gw->orig,
- primary_addr);
- if (is_own)
- continue;
- spin_lock_bh(&backbone_gw->crc_lock);
- backbone_crc = backbone_gw->crc;
- spin_unlock_bh(&backbone_gw->crc_lock);
- seq_printf(seq, " * %pM on %5d %4i.%03is (%#.4x)\n",
- backbone_gw->orig,
- batadv_print_vid(backbone_gw->vid), secs,
- msecs, backbone_crc);
- }
- rcu_read_unlock();
- }
- out:
- if (primary_if)
- batadv_hardif_put(primary_if);
- return 0;
- }
- #endif
- /**
- * 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)
- {
- 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:
- if (primary_if)
- batadv_hardif_put(primary_if);
- if (soft_iface)
- 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
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