| /* |
| * Copyright (C) 2011-2012 B.A.T.M.A.N. contributors: |
| * |
| * Simon Wunderlich |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of version 2 of the GNU General Public |
| * License as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| * 02110-1301, USA |
| * |
| */ |
| |
| #include "main.h" |
| #include "hash.h" |
| #include "hard-interface.h" |
| #include "originator.h" |
| #include "bridge_loop_avoidance.h" |
| #include "translation-table.h" |
| #include "send.h" |
| |
| #include <linux/etherdevice.h> |
| #include <linux/crc16.h> |
| #include <linux/if_arp.h> |
| #include <net/arp.h> |
| #include <linux/if_vlan.h> |
| |
| static const uint8_t announce_mac[4] = {0x43, 0x05, 0x43, 0x05}; |
| |
| static void bla_periodic_work(struct work_struct *work); |
| static void bla_send_announce(struct bat_priv *bat_priv, |
| struct backbone_gw *backbone_gw); |
| |
| /* return the index of the claim */ |
| static inline uint32_t choose_claim(const void *data, uint32_t size) |
| { |
| const unsigned char *key = data; |
| uint32_t hash = 0; |
| size_t i; |
| |
| for (i = 0; i < ETH_ALEN + sizeof(short); i++) { |
| hash += key[i]; |
| hash += (hash << 10); |
| hash ^= (hash >> 6); |
| } |
| |
| hash += (hash << 3); |
| hash ^= (hash >> 11); |
| hash += (hash << 15); |
| |
| return hash % size; |
| } |
| |
| /* return the index of the backbone gateway */ |
| static inline uint32_t choose_backbone_gw(const void *data, uint32_t size) |
| { |
| const unsigned char *key = data; |
| uint32_t hash = 0; |
| size_t i; |
| |
| for (i = 0; i < ETH_ALEN + sizeof(short); i++) { |
| hash += key[i]; |
| hash += (hash << 10); |
| hash ^= (hash >> 6); |
| } |
| |
| hash += (hash << 3); |
| hash ^= (hash >> 11); |
| hash += (hash << 15); |
| |
| return hash % size; |
| } |
| |
| |
| /* compares address and vid of two backbone gws */ |
| static int compare_backbone_gw(const struct hlist_node *node, const void *data2) |
| { |
| const void *data1 = container_of(node, struct backbone_gw, |
| hash_entry); |
| |
| return (memcmp(data1, data2, ETH_ALEN + sizeof(short)) == 0 ? 1 : 0); |
| } |
| |
| /* compares address and vid of two claims */ |
| static int compare_claim(const struct hlist_node *node, const void *data2) |
| { |
| const void *data1 = container_of(node, struct claim, |
| hash_entry); |
| |
| return (memcmp(data1, data2, ETH_ALEN + sizeof(short)) == 0 ? 1 : 0); |
| } |
| |
| /* free a backbone gw */ |
| static void backbone_gw_free_ref(struct backbone_gw *backbone_gw) |
| { |
| if (atomic_dec_and_test(&backbone_gw->refcount)) |
| kfree_rcu(backbone_gw, rcu); |
| } |
| |
| /* finally deinitialize the claim */ |
| static void claim_free_rcu(struct rcu_head *rcu) |
| { |
| struct claim *claim; |
| |
| claim = container_of(rcu, struct claim, rcu); |
| |
| backbone_gw_free_ref(claim->backbone_gw); |
| kfree(claim); |
| } |
| |
| /* free a claim, call claim_free_rcu if its the last reference */ |
| static void claim_free_ref(struct claim *claim) |
| { |
| if (atomic_dec_and_test(&claim->refcount)) |
| call_rcu(&claim->rcu, claim_free_rcu); |
| } |
| |
| /** |
| * @bat_priv: the bat priv with all the soft interface information |
| * @data: search data (may be local/static data) |
| * |
| * looks for a claim in the hash, and returns it if found |
| * or NULL otherwise. |
| */ |
| static struct claim *claim_hash_find(struct bat_priv *bat_priv, |
| struct claim *data) |
| { |
| struct hashtable_t *hash = bat_priv->claim_hash; |
| struct hlist_head *head; |
| struct hlist_node *node; |
| struct claim *claim; |
| struct claim *claim_tmp = NULL; |
| int index; |
| |
| if (!hash) |
| return NULL; |
| |
| index = choose_claim(data, hash->size); |
| head = &hash->table[index]; |
| |
| rcu_read_lock(); |
| hlist_for_each_entry_rcu(claim, node, head, hash_entry) { |
| if (!compare_claim(&claim->hash_entry, data)) |
| continue; |
| |
| if (!atomic_inc_not_zero(&claim->refcount)) |
| continue; |
| |
| claim_tmp = claim; |
| break; |
| } |
| rcu_read_unlock(); |
| |
| return claim_tmp; |
| } |
| |
| /** |
| * @bat_priv: the bat priv with all the soft interface information |
| * @addr: the address of the originator |
| * @vid: the VLAN ID |
| * |
| * looks for a claim in the hash, and returns it if found |
| * or NULL otherwise. |
| */ |
| static struct backbone_gw *backbone_hash_find(struct bat_priv *bat_priv, |
| uint8_t *addr, short vid) |
| { |
| struct hashtable_t *hash = bat_priv->backbone_hash; |
| struct hlist_head *head; |
| struct hlist_node *node; |
| struct backbone_gw search_entry, *backbone_gw; |
| struct backbone_gw *backbone_gw_tmp = NULL; |
| int index; |
| |
| if (!hash) |
| return NULL; |
| |
| memcpy(search_entry.orig, addr, ETH_ALEN); |
| search_entry.vid = vid; |
| |
| index = choose_backbone_gw(&search_entry, hash->size); |
| head = &hash->table[index]; |
| |
| rcu_read_lock(); |
| hlist_for_each_entry_rcu(backbone_gw, node, head, hash_entry) { |
| if (!compare_backbone_gw(&backbone_gw->hash_entry, |
| &search_entry)) |
| continue; |
| |
| if (!atomic_inc_not_zero(&backbone_gw->refcount)) |
| continue; |
| |
| backbone_gw_tmp = backbone_gw; |
| break; |
| } |
| rcu_read_unlock(); |
| |
| return backbone_gw_tmp; |
| } |
| |
| /* delete all claims for a backbone */ |
| static void bla_del_backbone_claims(struct backbone_gw *backbone_gw) |
| { |
| struct hashtable_t *hash; |
| struct hlist_node *node, *node_tmp; |
| struct hlist_head *head; |
| struct claim *claim; |
| int i; |
| spinlock_t *list_lock; /* protects write access to the hash lists */ |
| |
| hash = backbone_gw->bat_priv->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, node_tmp, |
| head, hash_entry) { |
| |
| if (claim->backbone_gw != backbone_gw) |
| continue; |
| |
| claim_free_ref(claim); |
| hlist_del_rcu(node); |
| } |
| spin_unlock_bh(list_lock); |
| } |
| |
| /* all claims gone, intialize CRC */ |
| backbone_gw->crc = BLA_CRC_INIT; |
| } |
| |
| /** |
| * @bat_priv: the bat priv with all the soft interface information |
| * @orig: the mac address to be announced within the claim |
| * @vid: the VLAN ID |
| * @claimtype: the type of the claim (CLAIM, UNCLAIM, ANNOUNCE, ...) |
| * |
| * sends a claim frame according to the provided info. |
| */ |
| static void bla_send_claim(struct bat_priv *bat_priv, uint8_t *mac, |
| short vid, int claimtype) |
| { |
| struct sk_buff *skb; |
| struct ethhdr *ethhdr; |
| struct hard_iface *primary_if; |
| struct net_device *soft_iface; |
| uint8_t *hw_src; |
| struct bla_claim_dst local_claim_dest; |
| __be32 zeroip = 0; |
| |
| primary_if = primary_if_get_selected(bat_priv); |
| if (!primary_if) |
| return; |
| |
| memcpy(&local_claim_dest, &bat_priv->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:00:00 |
| * with XX = claim type |
| * and YY:YY = group id |
| */ |
| (uint8_t *)&local_claim_dest); |
| |
| if (!skb) |
| goto out; |
| |
| ethhdr = (struct ethhdr *)skb->data; |
| hw_src = (uint8_t *)ethhdr + ETH_HLEN + sizeof(struct arphdr); |
| |
| /* now we pretend that the client would have sent this ... */ |
| switch (claimtype) { |
| case CLAIM_TYPE_ADD: |
| /* normal claim frame |
| * set Ethernet SRC to the clients mac |
| */ |
| memcpy(ethhdr->h_source, mac, ETH_ALEN); |
| bat_dbg(DBG_BLA, bat_priv, |
| "bla_send_claim(): CLAIM %pM on vid %d\n", mac, vid); |
| break; |
| case CLAIM_TYPE_DEL: |
| /* unclaim frame |
| * set HW SRC to the clients mac |
| */ |
| memcpy(hw_src, mac, ETH_ALEN); |
| bat_dbg(DBG_BLA, bat_priv, |
| "bla_send_claim(): UNCLAIM %pM on vid %d\n", mac, vid); |
| break; |
| case CLAIM_TYPE_ANNOUNCE: |
| /* announcement frame |
| * set HW SRC to the special mac containg the crc |
| */ |
| memcpy(hw_src, mac, ETH_ALEN); |
| bat_dbg(DBG_BLA, bat_priv, |
| "bla_send_claim(): ANNOUNCE of %pM on vid %d\n", |
| ethhdr->h_source, vid); |
| break; |
| case CLAIM_TYPE_REQUEST: |
| /* request frame |
| * set HW SRC to the special mac containg the crc |
| */ |
| memcpy(hw_src, mac, ETH_ALEN); |
| memcpy(ethhdr->h_dest, mac, ETH_ALEN); |
| bat_dbg(DBG_BLA, bat_priv, |
| "bla_send_claim(): REQUEST of %pM to %pMon vid %d\n", |
| ethhdr->h_source, ethhdr->h_dest, vid); |
| break; |
| |
| } |
| |
| if (vid != -1) |
| skb = vlan_insert_tag(skb, vid); |
| |
| skb_reset_mac_header(skb); |
| skb->protocol = eth_type_trans(skb, soft_iface); |
| bat_priv->stats.rx_packets++; |
| bat_priv->stats.rx_bytes += skb->len + ETH_HLEN; |
| soft_iface->last_rx = jiffies; |
| |
| netif_rx(skb); |
| out: |
| if (primary_if) |
| hardif_free_ref(primary_if); |
| } |
| |
| /** |
| * @bat_priv: the bat priv with all the soft interface information |
| * @orig: the mac address of the originator |
| * @vid: the VLAN ID |
| * |
| * searches for the backbone gw or creates a new one if it could not |
| * be found. |
| */ |
| static struct backbone_gw *bla_get_backbone_gw(struct bat_priv *bat_priv, |
| uint8_t *orig, short vid) |
| { |
| struct backbone_gw *entry; |
| struct orig_node *orig_node; |
| int hash_added; |
| |
| entry = backbone_hash_find(bat_priv, orig, vid); |
| |
| if (entry) |
| return entry; |
| |
| bat_dbg(DBG_BLA, bat_priv, |
| "bla_get_backbone_gw(): not found (%pM, %d), creating new entry\n", |
| orig, vid); |
| |
| entry = kzalloc(sizeof(*entry), GFP_ATOMIC); |
| if (!entry) |
| return NULL; |
| |
| entry->vid = vid; |
| entry->lasttime = jiffies; |
| entry->crc = BLA_CRC_INIT; |
| entry->bat_priv = bat_priv; |
| atomic_set(&entry->request_sent, 0); |
| memcpy(entry->orig, orig, ETH_ALEN); |
| |
| /* one for the hash, one for returning */ |
| atomic_set(&entry->refcount, 2); |
| |
| hash_added = hash_add(bat_priv->backbone_hash, compare_backbone_gw, |
| 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 entries */ |
| orig_node = orig_hash_find(bat_priv, orig); |
| if (orig_node) { |
| tt_global_del_orig(bat_priv, orig_node, |
| "became a backbone gateway"); |
| batadv_orig_node_free_ref(orig_node); |
| } |
| return entry; |
| } |
| |
| /* update or add the own backbone gw to make sure we announce |
| * where we receive other backbone gws |
| */ |
| static void bla_update_own_backbone_gw(struct bat_priv *bat_priv, |
| struct hard_iface *primary_if, |
| short vid) |
| { |
| struct backbone_gw *backbone_gw; |
| |
| backbone_gw = bla_get_backbone_gw(bat_priv, |
| primary_if->net_dev->dev_addr, vid); |
| if (unlikely(!backbone_gw)) |
| return; |
| |
| backbone_gw->lasttime = jiffies; |
| backbone_gw_free_ref(backbone_gw); |
| } |
| |
| /** |
| * @bat_priv: the bat priv with all the soft interface information |
| * @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 bla_answer_request(struct bat_priv *bat_priv, |
| struct hard_iface *primary_if, short vid) |
| { |
| struct hlist_node *node; |
| struct hlist_head *head; |
| struct hashtable_t *hash; |
| struct claim *claim; |
| struct backbone_gw *backbone_gw; |
| int i; |
| |
| bat_dbg(DBG_BLA, bat_priv, |
| "bla_answer_request(): received a claim request, send all of our own claims again\n"); |
| |
| backbone_gw = backbone_hash_find(bat_priv, |
| primary_if->net_dev->dev_addr, vid); |
| if (!backbone_gw) |
| return; |
| |
| hash = bat_priv->claim_hash; |
| for (i = 0; i < hash->size; i++) { |
| head = &hash->table[i]; |
| |
| rcu_read_lock(); |
| hlist_for_each_entry_rcu(claim, node, head, hash_entry) { |
| /* only own claims are interesting */ |
| if (claim->backbone_gw != backbone_gw) |
| continue; |
| |
| bla_send_claim(bat_priv, claim->addr, claim->vid, |
| CLAIM_TYPE_ADD); |
| } |
| rcu_read_unlock(); |
| } |
| |
| /* finally, send an announcement frame */ |
| bla_send_announce(bat_priv, backbone_gw); |
| backbone_gw_free_ref(backbone_gw); |
| } |
| |
| /** |
| * @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 bla_send_request(struct backbone_gw *backbone_gw) |
| { |
| /* first, remove all old entries */ |
| bla_del_backbone_claims(backbone_gw); |
| |
| bat_dbg(DBG_BLA, backbone_gw->bat_priv, |
| "Sending REQUEST to %pM\n", |
| backbone_gw->orig); |
| |
| /* send request */ |
| bla_send_claim(backbone_gw->bat_priv, backbone_gw->orig, |
| backbone_gw->vid, 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); |
| } |
| } |
| |
| /** |
| * @bat_priv: the bat priv with all the soft interface information |
| * @backbone_gw: our backbone gateway which should be announced |
| * |
| * This function sends an announcement. It is called from multiple |
| * places. |
| */ |
| static void bla_send_announce(struct bat_priv *bat_priv, |
| struct backbone_gw *backbone_gw) |
| { |
| uint8_t mac[ETH_ALEN]; |
| __be16 crc; |
| |
| memcpy(mac, announce_mac, 4); |
| crc = htons(backbone_gw->crc); |
| memcpy(&mac[4], &crc, 2); |
| |
| bla_send_claim(bat_priv, mac, backbone_gw->vid, CLAIM_TYPE_ANNOUNCE); |
| |
| } |
| |
| /** |
| * @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 |
| * |
| * Adds a claim in the claim hash. |
| */ |
| static void bla_add_claim(struct bat_priv *bat_priv, const uint8_t *mac, |
| const short vid, struct backbone_gw *backbone_gw) |
| { |
| struct claim *claim; |
| struct claim search_claim; |
| int hash_added; |
| |
| memcpy(search_claim.addr, mac, ETH_ALEN); |
| search_claim.vid = vid; |
| claim = 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; |
| |
| memcpy(claim->addr, mac, ETH_ALEN); |
| claim->vid = vid; |
| claim->lasttime = jiffies; |
| claim->backbone_gw = backbone_gw; |
| |
| atomic_set(&claim->refcount, 2); |
| bat_dbg(DBG_BLA, bat_priv, |
| "bla_add_claim(): adding new entry %pM, vid %d to hash ...\n", |
| mac, vid); |
| hash_added = hash_add(bat_priv->claim_hash, compare_claim, |
| 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; |
| |
| bat_dbg(DBG_BLA, bat_priv, |
| "bla_add_claim(): changing ownership for %pM, vid %d\n", |
| mac, vid); |
| |
| claim->backbone_gw->crc ^= |
| crc16(0, claim->addr, ETH_ALEN); |
| backbone_gw_free_ref(claim->backbone_gw); |
| |
| } |
| /* set (new) backbone gw */ |
| atomic_inc(&backbone_gw->refcount); |
| claim->backbone_gw = backbone_gw; |
| |
| backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN); |
| backbone_gw->lasttime = jiffies; |
| |
| claim_free_ref: |
| claim_free_ref(claim); |
| } |
| |
| /* Delete a claim from the claim hash which has the |
| * given mac address and vid. |
| */ |
| static void bla_del_claim(struct bat_priv *bat_priv, const uint8_t *mac, |
| const short vid) |
| { |
| struct claim search_claim, *claim; |
| |
| memcpy(search_claim.addr, mac, ETH_ALEN); |
| search_claim.vid = vid; |
| claim = claim_hash_find(bat_priv, &search_claim); |
| if (!claim) |
| return; |
| |
| bat_dbg(DBG_BLA, bat_priv, "bla_del_claim(): %pM, vid %d\n", mac, vid); |
| |
| hash_remove(bat_priv->claim_hash, compare_claim, choose_claim, claim); |
| claim_free_ref(claim); /* reference from the hash is gone */ |
| |
| claim->backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN); |
| |
| /* don't need the reference from hash_find() anymore */ |
| claim_free_ref(claim); |
| } |
| |
| /* check for ANNOUNCE frame, return 1 if handled */ |
| static int handle_announce(struct bat_priv *bat_priv, |
| uint8_t *an_addr, uint8_t *backbone_addr, short vid) |
| { |
| struct backbone_gw *backbone_gw; |
| uint16_t crc; |
| |
| if (memcmp(an_addr, announce_mac, 4) != 0) |
| return 0; |
| |
| backbone_gw = bla_get_backbone_gw(bat_priv, backbone_addr, vid); |
| |
| if (unlikely(!backbone_gw)) |
| return 1; |
| |
| |
| /* handle as ANNOUNCE frame */ |
| backbone_gw->lasttime = jiffies; |
| crc = ntohs(*((__be16 *)(&an_addr[4]))); |
| |
| bat_dbg(DBG_BLA, bat_priv, |
| "handle_announce(): ANNOUNCE vid %d (sent by %pM)... CRC = %04x\n", |
| vid, backbone_gw->orig, crc); |
| |
| if (backbone_gw->crc != crc) { |
| bat_dbg(DBG_BLA, backbone_gw->bat_priv, |
| "handle_announce(): CRC FAILED for %pM/%d (my = %04x, sent = %04x)\n", |
| backbone_gw->orig, backbone_gw->vid, backbone_gw->crc, |
| crc); |
| |
| 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); |
| } |
| } |
| |
| backbone_gw_free_ref(backbone_gw); |
| return 1; |
| } |
| |
| /* check for REQUEST frame, return 1 if handled */ |
| static int handle_request(struct bat_priv *bat_priv, |
| struct hard_iface *primary_if, |
| uint8_t *backbone_addr, |
| struct ethhdr *ethhdr, short vid) |
| { |
| /* check for REQUEST frame */ |
| if (!compare_eth(backbone_addr, ethhdr->h_dest)) |
| return 0; |
| |
| /* sanity check, this should not happen on a normal switch, |
| * we ignore it in this case. |
| */ |
| if (!compare_eth(ethhdr->h_dest, primary_if->net_dev->dev_addr)) |
| return 1; |
| |
| bat_dbg(DBG_BLA, bat_priv, |
| "handle_request(): REQUEST vid %d (sent by %pM)...\n", |
| vid, ethhdr->h_source); |
| |
| bla_answer_request(bat_priv, primary_if, vid); |
| return 1; |
| } |
| |
| /* check for UNCLAIM frame, return 1 if handled */ |
| static int handle_unclaim(struct bat_priv *bat_priv, |
| struct hard_iface *primary_if, |
| uint8_t *backbone_addr, |
| uint8_t *claim_addr, short vid) |
| { |
| struct backbone_gw *backbone_gw; |
| |
| /* unclaim in any case if it is our own */ |
| if (primary_if && compare_eth(backbone_addr, |
| primary_if->net_dev->dev_addr)) |
| bla_send_claim(bat_priv, claim_addr, vid, CLAIM_TYPE_DEL); |
| |
| backbone_gw = backbone_hash_find(bat_priv, backbone_addr, vid); |
| |
| if (!backbone_gw) |
| return 1; |
| |
| /* this must be an UNCLAIM frame */ |
| bat_dbg(DBG_BLA, bat_priv, |
| "handle_unclaim(): UNCLAIM %pM on vid %d (sent by %pM)...\n", |
| claim_addr, vid, backbone_gw->orig); |
| |
| bla_del_claim(bat_priv, claim_addr, vid); |
| backbone_gw_free_ref(backbone_gw); |
| return 1; |
| } |
| |
| /* check for CLAIM frame, return 1 if handled */ |
| static int handle_claim(struct bat_priv *bat_priv, |
| struct hard_iface *primary_if, uint8_t *backbone_addr, |
| uint8_t *claim_addr, short vid) |
| { |
| struct backbone_gw *backbone_gw; |
| |
| /* register the gateway if not yet available, and add the claim. */ |
| |
| backbone_gw = bla_get_backbone_gw(bat_priv, backbone_addr, vid); |
| |
| if (unlikely(!backbone_gw)) |
| return 1; |
| |
| /* this must be a CLAIM frame */ |
| bla_add_claim(bat_priv, claim_addr, vid, backbone_gw); |
| if (compare_eth(backbone_addr, primary_if->net_dev->dev_addr)) |
| bla_send_claim(bat_priv, claim_addr, vid, CLAIM_TYPE_ADD); |
| |
| /* TODO: we could call something like tt_local_del() here. */ |
| |
| backbone_gw_free_ref(backbone_gw); |
| return 1; |
| } |
| |
| /** |
| * @bat_priv: the bat priv with all the soft interface information |
| * @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 its on the same group. |
| * This function also applies the group ID of the sender |
| * if it is in the same mesh. |
| * |
| * returns: |
| * 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 check_claim_group(struct bat_priv *bat_priv, |
| struct hard_iface *primary_if, |
| uint8_t *hw_src, uint8_t *hw_dst, |
| struct ethhdr *ethhdr) |
| { |
| uint8_t *backbone_addr; |
| struct orig_node *orig_node; |
| struct bla_claim_dst *bla_dst, *bla_dst_own; |
| |
| bla_dst = (struct bla_claim_dst *)hw_dst; |
| bla_dst_own = &bat_priv->claim_dest; |
| |
| /* check if it is a claim packet in general */ |
| if (memcmp(bla_dst->magic, bla_dst_own->magic, |
| sizeof(bla_dst->magic)) != 0) |
| return 0; |
| |
| /* if announcement packet, use the source, |
| * otherwise assume it is in the hw_src |
| */ |
| switch (bla_dst->type) { |
| case CLAIM_TYPE_ADD: |
| backbone_addr = hw_src; |
| break; |
| case CLAIM_TYPE_REQUEST: |
| case CLAIM_TYPE_ANNOUNCE: |
| case CLAIM_TYPE_DEL: |
| backbone_addr = ethhdr->h_source; |
| break; |
| default: |
| return 0; |
| } |
| |
| /* don't accept claim frames from ourselves */ |
| if (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 = 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)) { |
| bat_dbg(DBG_BLA, bat_priv, |
| "taking other backbones claim group: %04x\n", |
| ntohs(bla_dst->group)); |
| bla_dst_own->group = bla_dst->group; |
| } |
| |
| batadv_orig_node_free_ref(orig_node); |
| |
| return 2; |
| } |
| |
| |
| /** |
| * @bat_priv: the bat priv with all the soft interface information |
| * @skb: the frame to be checked |
| * |
| * Check if this is a claim frame, and process it accordingly. |
| * |
| * returns 1 if it was a claim frame, otherwise return 0 to |
| * tell the callee that it can use the frame on its own. |
| */ |
| static int bla_process_claim(struct bat_priv *bat_priv, |
| struct hard_iface *primary_if, |
| struct sk_buff *skb) |
| { |
| struct ethhdr *ethhdr; |
| struct vlan_ethhdr *vhdr; |
| struct arphdr *arphdr; |
| uint8_t *hw_src, *hw_dst; |
| struct bla_claim_dst *bla_dst; |
| uint16_t proto; |
| int headlen; |
| short vid = -1; |
| int ret; |
| |
| ethhdr = (struct ethhdr *)skb_mac_header(skb); |
| |
| if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) { |
| vhdr = (struct vlan_ethhdr *)ethhdr; |
| vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK; |
| proto = ntohs(vhdr->h_vlan_encapsulated_proto); |
| headlen = sizeof(*vhdr); |
| } else { |
| proto = ntohs(ethhdr->h_proto); |
| headlen = ETH_HLEN; |
| } |
| |
| if (proto != ETH_P_ARP) |
| return 0; /* 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 0; |
| |
| /* pskb_may_pull() may have modified the pointers, get ethhdr again */ |
| ethhdr = (struct ethhdr *)skb_mac_header(skb); |
| arphdr = (struct arphdr *)((uint8_t *)ethhdr + headlen); |
| |
| /* Check whether the ARP frame carries a valid |
| * IP information |
| */ |
| |
| if (arphdr->ar_hrd != htons(ARPHRD_ETHER)) |
| return 0; |
| if (arphdr->ar_pro != htons(ETH_P_IP)) |
| return 0; |
| if (arphdr->ar_hln != ETH_ALEN) |
| return 0; |
| if (arphdr->ar_pln != 4) |
| return 0; |
| |
| hw_src = (uint8_t *)arphdr + sizeof(struct arphdr); |
| hw_dst = hw_src + ETH_ALEN + 4; |
| bla_dst = (struct bla_claim_dst *)hw_dst; |
| |
| /* check if it is a claim frame. */ |
| ret = check_claim_group(bat_priv, primary_if, hw_src, hw_dst, ethhdr); |
| if (ret == 1) |
| bat_dbg(DBG_BLA, bat_priv, |
| "bla_process_claim(): received a claim frame from another group. From: %pM on vid %d ...(hw_src %pM, hw_dst %pM)\n", |
| ethhdr->h_source, vid, hw_src, hw_dst); |
| |
| if (ret < 2) |
| return ret; |
| |
| /* become a backbone gw ourselves on this vlan if not happened yet */ |
| bla_update_own_backbone_gw(bat_priv, primary_if, vid); |
| |
| /* check for the different types of claim frames ... */ |
| switch (bla_dst->type) { |
| case CLAIM_TYPE_ADD: |
| if (handle_claim(bat_priv, primary_if, hw_src, |
| ethhdr->h_source, vid)) |
| return 1; |
| break; |
| case CLAIM_TYPE_DEL: |
| if (handle_unclaim(bat_priv, primary_if, |
| ethhdr->h_source, hw_src, vid)) |
| return 1; |
| break; |
| |
| case CLAIM_TYPE_ANNOUNCE: |
| if (handle_announce(bat_priv, hw_src, ethhdr->h_source, vid)) |
| return 1; |
| break; |
| case CLAIM_TYPE_REQUEST: |
| if (handle_request(bat_priv, primary_if, hw_src, ethhdr, vid)) |
| return 1; |
| break; |
| } |
| |
| bat_dbg(DBG_BLA, bat_priv, |
| "bla_process_claim(): ERROR - this looks like a claim frame, but is useless. eth src %pM on vid %d ...(hw_src %pM, hw_dst %pM)\n", |
| ethhdr->h_source, vid, hw_src, hw_dst); |
| return 1; |
| } |
| |
| /* 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 bla_purge_backbone_gw(struct bat_priv *bat_priv, int now) |
| { |
| struct backbone_gw *backbone_gw; |
| struct hlist_node *node, *node_tmp; |
| struct hlist_head *head; |
| struct hashtable_t *hash; |
| spinlock_t *list_lock; /* protects write access to the hash lists */ |
| int i; |
| |
| hash = bat_priv->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, node_tmp, |
| head, hash_entry) { |
| if (now) |
| goto purge_now; |
| if (!has_timed_out(backbone_gw->lasttime, |
| BLA_BACKBONE_TIMEOUT)) |
| continue; |
| |
| bat_dbg(DBG_BLA, backbone_gw->bat_priv, |
| "bla_purge_backbone_gw(): backbone gw %pM timed out\n", |
| 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); |
| |
| bla_del_backbone_claims(backbone_gw); |
| |
| hlist_del_rcu(node); |
| backbone_gw_free_ref(backbone_gw); |
| } |
| spin_unlock_bh(list_lock); |
| } |
| } |
| |
| /** |
| * @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 bla_purge_claims(struct bat_priv *bat_priv, |
| struct hard_iface *primary_if, int now) |
| { |
| struct claim *claim; |
| struct hlist_node *node; |
| struct hlist_head *head; |
| struct hashtable_t *hash; |
| int i; |
| |
| hash = bat_priv->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, node, head, hash_entry) { |
| if (now) |
| goto purge_now; |
| if (!compare_eth(claim->backbone_gw->orig, |
| primary_if->net_dev->dev_addr)) |
| continue; |
| if (!has_timed_out(claim->lasttime, |
| BLA_CLAIM_TIMEOUT)) |
| continue; |
| |
| bat_dbg(DBG_BLA, bat_priv, |
| "bla_purge_claims(): %pM, vid %d, time out\n", |
| claim->addr, claim->vid); |
| |
| purge_now: |
| handle_unclaim(bat_priv, primary_if, |
| claim->backbone_gw->orig, |
| claim->addr, claim->vid); |
| } |
| rcu_read_unlock(); |
| } |
| } |
| |
| /** |
| * @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 |
| * |
| * Update the backbone gateways when the own orig address changes. |
| * |
| */ |
| void batadv_bla_update_orig_address(struct bat_priv *bat_priv, |
| struct hard_iface *primary_if, |
| struct hard_iface *oldif) |
| { |
| struct backbone_gw *backbone_gw; |
| struct hlist_node *node; |
| struct hlist_head *head; |
| struct hashtable_t *hash; |
| int i; |
| |
| /* reset bridge loop avoidance group id */ |
| bat_priv->claim_dest.group = |
| htons(crc16(0, primary_if->net_dev->dev_addr, ETH_ALEN)); |
| |
| if (!oldif) { |
| bla_purge_claims(bat_priv, NULL, 1); |
| bla_purge_backbone_gw(bat_priv, 1); |
| return; |
| } |
| |
| hash = bat_priv->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, node, head, hash_entry) { |
| /* own orig still holds the old value. */ |
| if (!compare_eth(backbone_gw->orig, |
| oldif->net_dev->dev_addr)) |
| continue; |
| |
| memcpy(backbone_gw->orig, |
| primary_if->net_dev->dev_addr, ETH_ALEN); |
| /* send an announce frame so others will ask for our |
| * claims and update their tables. |
| */ |
| bla_send_announce(bat_priv, backbone_gw); |
| } |
| rcu_read_unlock(); |
| } |
| } |
| |
| |
| |
| /* (re)start the timer */ |
| static void bla_start_timer(struct bat_priv *bat_priv) |
| { |
| INIT_DELAYED_WORK(&bat_priv->bla_work, bla_periodic_work); |
| queue_delayed_work(bat_event_workqueue, &bat_priv->bla_work, |
| msecs_to_jiffies(BLA_PERIOD_LENGTH)); |
| } |
| |
| /* periodic work to do: |
| * * purge structures when they are too old |
| * * send announcements |
| */ |
| static void bla_periodic_work(struct work_struct *work) |
| { |
| struct delayed_work *delayed_work = |
| container_of(work, struct delayed_work, work); |
| struct bat_priv *bat_priv = |
| container_of(delayed_work, struct bat_priv, bla_work); |
| struct hlist_node *node; |
| struct hlist_head *head; |
| struct backbone_gw *backbone_gw; |
| struct hashtable_t *hash; |
| struct hard_iface *primary_if; |
| int i; |
| |
| primary_if = primary_if_get_selected(bat_priv); |
| if (!primary_if) |
| goto out; |
| |
| bla_purge_claims(bat_priv, primary_if, 0); |
| bla_purge_backbone_gw(bat_priv, 0); |
| |
| if (!atomic_read(&bat_priv->bridge_loop_avoidance)) |
| goto out; |
| |
| hash = bat_priv->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, node, head, hash_entry) { |
| if (!compare_eth(backbone_gw->orig, |
| primary_if->net_dev->dev_addr)) |
| continue; |
| |
| backbone_gw->lasttime = jiffies; |
| |
| bla_send_announce(bat_priv, backbone_gw); |
| } |
| rcu_read_unlock(); |
| } |
| out: |
| if (primary_if) |
| hardif_free_ref(primary_if); |
| |
| bla_start_timer(bat_priv); |
| } |
| |
| /* 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 claim_hash_lock_class_key; |
| static struct lock_class_key backbone_hash_lock_class_key; |
| |
| /* initialize all bla structures */ |
| int batadv_bla_init(struct bat_priv *bat_priv) |
| { |
| int i; |
| uint8_t claim_dest[ETH_ALEN] = {0xff, 0x43, 0x05, 0x00, 0x00, 0x00}; |
| struct hard_iface *primary_if; |
| |
| bat_dbg(DBG_BLA, bat_priv, "bla hash registering\n"); |
| |
| /* setting claim destination address */ |
| memcpy(&bat_priv->claim_dest.magic, claim_dest, 3); |
| bat_priv->claim_dest.type = 0; |
| primary_if = primary_if_get_selected(bat_priv); |
| if (primary_if) { |
| bat_priv->claim_dest.group = |
| htons(crc16(0, primary_if->net_dev->dev_addr, |
| ETH_ALEN)); |
| hardif_free_ref(primary_if); |
| } else { |
| bat_priv->claim_dest.group = 0; /* will be set later */ |
| } |
| |
| /* initialize the duplicate list */ |
| for (i = 0; i < DUPLIST_SIZE; i++) |
| bat_priv->bcast_duplist[i].entrytime = |
| jiffies - msecs_to_jiffies(DUPLIST_TIMEOUT); |
| bat_priv->bcast_duplist_curr = 0; |
| |
| if (bat_priv->claim_hash) |
| return 0; |
| |
| bat_priv->claim_hash = batadv_hash_new(128); |
| bat_priv->backbone_hash = batadv_hash_new(32); |
| |
| if (!bat_priv->claim_hash || !bat_priv->backbone_hash) |
| return -ENOMEM; |
| |
| batadv_hash_set_lock_class(bat_priv->claim_hash, |
| &claim_hash_lock_class_key); |
| batadv_hash_set_lock_class(bat_priv->backbone_hash, |
| &backbone_hash_lock_class_key); |
| |
| bat_dbg(DBG_BLA, bat_priv, "bla hashes initialized\n"); |
| |
| bla_start_timer(bat_priv); |
| return 0; |
| } |
| |
| /** |
| * @bat_priv: the bat priv with all the soft interface information |
| * @bcast_packet: originator mac address |
| * @hdr_size: maximum length of the frame |
| * |
| * 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. |
| * |
| **/ |
| |
| int batadv_bla_check_bcast_duplist(struct bat_priv *bat_priv, |
| struct bcast_packet *bcast_packet, |
| int hdr_size) |
| { |
| int i, length, curr; |
| uint8_t *content; |
| uint16_t crc; |
| struct bcast_duplist_entry *entry; |
| |
| length = hdr_size - sizeof(*bcast_packet); |
| content = (uint8_t *)bcast_packet; |
| content += sizeof(*bcast_packet); |
| |
| /* calculate the crc ... */ |
| crc = crc16(0, content, length); |
| |
| for (i = 0 ; i < DUPLIST_SIZE; i++) { |
| curr = (bat_priv->bcast_duplist_curr + i) % DUPLIST_SIZE; |
| entry = &bat_priv->bcast_duplist[curr]; |
| |
| /* we can stop searching if the entry is too old ; |
| * later entries will be even older |
| */ |
| if (has_timed_out(entry->entrytime, DUPLIST_TIMEOUT)) |
| break; |
| |
| if (entry->crc != crc) |
| continue; |
| |
| if (compare_eth(entry->orig, bcast_packet->orig)) |
| continue; |
| |
| /* this entry seems to match: same crc, not too old, |
| * and from another gw. therefore return 1 to forbid it. |
| */ |
| return 1; |
| } |
| /* not found, add a new entry (overwrite the oldest entry) */ |
| curr = (bat_priv->bcast_duplist_curr + DUPLIST_SIZE - 1) % DUPLIST_SIZE; |
| entry = &bat_priv->bcast_duplist[curr]; |
| entry->crc = crc; |
| entry->entrytime = jiffies; |
| memcpy(entry->orig, bcast_packet->orig, ETH_ALEN); |
| bat_priv->bcast_duplist_curr = curr; |
| |
| /* allow it, its the first occurence. */ |
| return 0; |
| } |
| |
| |
| |
| /** |
| * @bat_priv: the bat priv with all the soft interface information |
| * @orig: originator mac address |
| * |
| * check if the originator is a gateway for any VLAN ID. |
| * |
| * returns 1 if it is found, 0 otherwise |
| * |
| */ |
| |
| int batadv_bla_is_backbone_gw_orig(struct bat_priv *bat_priv, uint8_t *orig) |
| { |
| struct hashtable_t *hash = bat_priv->backbone_hash; |
| struct hlist_head *head; |
| struct hlist_node *node; |
| struct backbone_gw *backbone_gw; |
| int i; |
| |
| if (!atomic_read(&bat_priv->bridge_loop_avoidance)) |
| return 0; |
| |
| if (!hash) |
| return 0; |
| |
| for (i = 0; i < hash->size; i++) { |
| head = &hash->table[i]; |
| |
| rcu_read_lock(); |
| hlist_for_each_entry_rcu(backbone_gw, node, head, hash_entry) { |
| if (compare_eth(backbone_gw->orig, orig)) { |
| rcu_read_unlock(); |
| return 1; |
| } |
| } |
| rcu_read_unlock(); |
| } |
| |
| return 0; |
| } |
| |
| |
| /** |
| * @skb: the frame to be checked |
| * @orig_node: the orig_node of the frame |
| * @hdr_size: maximum length of the frame |
| * |
| * bla_is_backbone_gw inspects the skb for the VLAN ID and returns 1 |
| * if the orig_node is also a gateway on the soft interface, otherwise it |
| * returns 0. |
| * |
| */ |
| int batadv_bla_is_backbone_gw(struct sk_buff *skb, |
| struct orig_node *orig_node, int hdr_size) |
| { |
| struct ethhdr *ethhdr; |
| struct vlan_ethhdr *vhdr; |
| struct backbone_gw *backbone_gw; |
| short vid = -1; |
| |
| if (!atomic_read(&orig_node->bat_priv->bridge_loop_avoidance)) |
| return 0; |
| |
| /* first, find out the vid. */ |
| if (!pskb_may_pull(skb, hdr_size + ETH_HLEN)) |
| return 0; |
| |
| ethhdr = (struct ethhdr *)(((uint8_t *)skb->data) + hdr_size); |
| |
| if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) { |
| if (!pskb_may_pull(skb, hdr_size + sizeof(struct vlan_ethhdr))) |
| return 0; |
| |
| vhdr = (struct vlan_ethhdr *)(((uint8_t *)skb->data) + |
| hdr_size); |
| vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK; |
| } |
| |
| /* see if this originator is a backbone gw for this VLAN */ |
| |
| backbone_gw = backbone_hash_find(orig_node->bat_priv, |
| orig_node->orig, vid); |
| if (!backbone_gw) |
| return 0; |
| |
| backbone_gw_free_ref(backbone_gw); |
| return 1; |
| } |
| |
| /* free all bla structures (for softinterface free or module unload) */ |
| void batadv_bla_free(struct bat_priv *bat_priv) |
| { |
| struct hard_iface *primary_if; |
| |
| cancel_delayed_work_sync(&bat_priv->bla_work); |
| primary_if = primary_if_get_selected(bat_priv); |
| |
| if (bat_priv->claim_hash) { |
| bla_purge_claims(bat_priv, primary_if, 1); |
| batadv_hash_destroy(bat_priv->claim_hash); |
| bat_priv->claim_hash = NULL; |
| } |
| if (bat_priv->backbone_hash) { |
| bla_purge_backbone_gw(bat_priv, 1); |
| batadv_hash_destroy(bat_priv->backbone_hash); |
| bat_priv->backbone_hash = NULL; |
| } |
| if (primary_if) |
| hardif_free_ref(primary_if); |
| } |
| |
| /** |
| * @bat_priv: the bat priv with all the soft interface information |
| * @skb: the frame to be checked |
| * @vid: the VLAN ID of the frame |
| * |
| * 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 and |
| * returns 1, otherwise it returns 0 and the caller shall further |
| * process the skb. |
| * |
| */ |
| int batadv_bla_rx(struct bat_priv *bat_priv, struct sk_buff *skb, short vid) |
| { |
| struct ethhdr *ethhdr; |
| struct claim search_claim, *claim = NULL; |
| struct hard_iface *primary_if; |
| int ret; |
| |
| ethhdr = (struct ethhdr *)skb_mac_header(skb); |
| |
| primary_if = primary_if_get_selected(bat_priv); |
| if (!primary_if) |
| goto handled; |
| |
| if (!atomic_read(&bat_priv->bridge_loop_avoidance)) |
| goto allow; |
| |
| |
| 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; |
| |
| memcpy(search_claim.addr, ethhdr->h_source, ETH_ALEN); |
| search_claim.vid = vid; |
| claim = claim_hash_find(bat_priv, &search_claim); |
| |
| if (!claim) { |
| /* possible optimization: race for a claim */ |
| /* No claim exists yet, claim it for us! |
| */ |
| handle_claim(bat_priv, primary_if, |
| primary_if->net_dev->dev_addr, |
| ethhdr->h_source, vid); |
| goto allow; |
| } |
| |
| /* if it is our own claim ... */ |
| if (compare_eth(claim->backbone_gw->orig, |
| primary_if->net_dev->dev_addr)) { |
| /* ... allow it in any case */ |
| claim->lasttime = jiffies; |
| goto allow; |
| } |
| |
| /* if it is a broadcast ... */ |
| if (is_multicast_ether_addr(ethhdr->h_dest)) { |
| /* ... drop it. the responsible gateway is in charge. */ |
| goto handled; |
| } else { |
| /* seems the client considers us as its best gateway. |
| * send a claim and update the claim table |
| * immediately. |
| */ |
| handle_claim(bat_priv, primary_if, |
| primary_if->net_dev->dev_addr, |
| ethhdr->h_source, vid); |
| goto allow; |
| } |
| allow: |
| bla_update_own_backbone_gw(bat_priv, primary_if, vid); |
| ret = 0; |
| goto out; |
| |
| handled: |
| kfree_skb(skb); |
| ret = 1; |
| |
| out: |
| if (primary_if) |
| hardif_free_ref(primary_if); |
| if (claim) |
| claim_free_ref(claim); |
| return ret; |
| } |
| |
| /** |
| * @bat_priv: the bat priv with all the soft interface information |
| * @skb: the frame to be checked |
| * @vid: the VLAN ID of the frame |
| * |
| * 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 and |
| * returns 1, otherwise it returns 0 and the caller shall further |
| * process the skb. |
| * |
| */ |
| int batadv_bla_tx(struct bat_priv *bat_priv, struct sk_buff *skb, short vid) |
| { |
| struct ethhdr *ethhdr; |
| struct claim search_claim, *claim = NULL; |
| struct hard_iface *primary_if; |
| int ret = 0; |
| |
| primary_if = primary_if_get_selected(bat_priv); |
| if (!primary_if) |
| goto out; |
| |
| if (!atomic_read(&bat_priv->bridge_loop_avoidance)) |
| goto allow; |
| |
| /* in VLAN case, the mac header might not be set. */ |
| skb_reset_mac_header(skb); |
| |
| if (bla_process_claim(bat_priv, primary_if, skb)) |
| goto handled; |
| |
| ethhdr = (struct ethhdr *)skb_mac_header(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; |
| |
| memcpy(search_claim.addr, ethhdr->h_source, ETH_ALEN); |
| search_claim.vid = vid; |
| |
| claim = claim_hash_find(bat_priv, &search_claim); |
| |
| /* if no claim exists, allow it. */ |
| if (!claim) |
| goto allow; |
| |
| /* check if we are responsible. */ |
| if (compare_eth(claim->backbone_gw->orig, |
| primary_if->net_dev->dev_addr)) { |
| /* if yes, the client has roamed and we have |
| * to unclaim it. |
| */ |
| handle_unclaim(bat_priv, primary_if, |
| primary_if->net_dev->dev_addr, |
| ethhdr->h_source, vid); |
| goto allow; |
| } |
| |
| /* 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: |
| bla_update_own_backbone_gw(bat_priv, primary_if, vid); |
| ret = 0; |
| goto out; |
| handled: |
| ret = 1; |
| out: |
| if (primary_if) |
| hardif_free_ref(primary_if); |
| if (claim) |
| claim_free_ref(claim); |
| return ret; |
| } |
| |
| 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 bat_priv *bat_priv = netdev_priv(net_dev); |
| struct hashtable_t *hash = bat_priv->claim_hash; |
| struct claim *claim; |
| struct hard_iface *primary_if; |
| struct hlist_node *node; |
| struct hlist_head *head; |
| uint32_t i; |
| bool is_own; |
| int ret = 0; |
| |
| primary_if = primary_if_get_selected(bat_priv); |
| if (!primary_if) { |
| ret = seq_printf(seq, |
| "BATMAN mesh %s disabled - please specify interfaces to enable it\n", |
| net_dev->name); |
| goto out; |
| } |
| |
| if (primary_if->if_status != IF_ACTIVE) { |
| ret = seq_printf(seq, |
| "BATMAN mesh %s disabled - primary interface not active\n", |
| net_dev->name); |
| goto out; |
| } |
| |
| seq_printf(seq, |
| "Claims announced for the mesh %s (orig %pM, group id %04x)\n", |
| net_dev->name, primary_if->net_dev->dev_addr, |
| ntohs(bat_priv->claim_dest.group)); |
| seq_printf(seq, " %-17s %-5s %-17s [o] (%-4s)\n", |
| "Client", "VID", "Originator", "CRC"); |
| for (i = 0; i < hash->size; i++) { |
| head = &hash->table[i]; |
| |
| rcu_read_lock(); |
| hlist_for_each_entry_rcu(claim, node, head, hash_entry) { |
| is_own = compare_eth(claim->backbone_gw->orig, |
| primary_if->net_dev->dev_addr); |
| seq_printf(seq, " * %pM on % 5d by %pM [%c] (%04x)\n", |
| claim->addr, claim->vid, |
| claim->backbone_gw->orig, |
| (is_own ? 'x' : ' '), |
| claim->backbone_gw->crc); |
| } |
| rcu_read_unlock(); |
| } |
| out: |
| if (primary_if) |
| hardif_free_ref(primary_if); |
| return ret; |
| } |