/* check for CLAIM frame, return 1 if handled */ static int batadv_handle_claim(struct batadv_priv *bat_priv, struct batadv_hard_iface *primary_if, uint8_t *backbone_addr, uint8_t *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 1; /* 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_free_ref(backbone_gw); return 1; }
/** * batadv_bla_is_backbone_gw * @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 batadv_orig_node *orig_node, int hdr_size) { struct ethhdr *ethhdr; struct vlan_ethhdr *vhdr; struct batadv_bla_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 *)(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 = batadv_backbone_hash_find(orig_node->bat_priv, orig_node->orig, vid); if (!backbone_gw) return 0; batadv_backbone_gw_free_ref(backbone_gw); return 1; }
/* check for UNCLAIM frame, return 1 if handled */ static int batadv_handle_unclaim(struct batadv_priv *bat_priv, struct batadv_hard_iface *primary_if, uint8_t *backbone_addr, uint8_t *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 1; /* this must be an UNCLAIM frame */ batadv_dbg(BATADV_DBG_BLA, bat_priv, "handle_unclaim(): UNCLAIM %pM on vid %d (sent by %pM)...\n", claim_addr, BATADV_PRINT_VID(vid), backbone_gw->orig); batadv_bla_del_claim(bat_priv, claim_addr, vid); batadv_backbone_gw_free_ref(backbone_gw); return 1; }
/** * 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 uint8_t *mac, const unsigned short vid, struct batadv_bla_backbone_gw *backbone_gw) { struct batadv_bla_claim *claim; struct batadv_bla_claim search_claim; 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); claim->vid = vid; claim->lasttime = jiffies; claim->backbone_gw = backbone_gw; atomic_set(&claim->refcount, 2); batadv_dbg(BATADV_DBG_BLA, bat_priv, "bla_add_claim(): adding new entry %pM, vid %d to hash ...\n", mac, BATADV_PRINT_VID(vid)); 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, "bla_add_claim(): changing ownership for %pM, vid %d\n", mac, BATADV_PRINT_VID(vid)); claim->backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN); batadv_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: batadv_claim_free_ref(claim); }
/* finally deinitialize the claim */ static void batadv_claim_free_rcu(struct rcu_head *rcu) { struct batadv_bla_claim *claim; claim = container_of(rcu, struct batadv_bla_claim, rcu); batadv_backbone_gw_free_ref(claim->backbone_gw); kfree(claim); }
/* 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_free_ref(backbone_gw); }
/* check for ANNOUNCE frame, return 1 if handled */ static int batadv_handle_announce(struct batadv_priv *bat_priv, uint8_t *an_addr, uint8_t *backbone_addr, unsigned short vid) { struct batadv_bla_backbone_gw *backbone_gw; uint16_t crc; if (memcmp(an_addr, batadv_announce_mac, 4) != 0) return 0; backbone_gw = batadv_bla_get_backbone_gw(bat_priv, backbone_addr, vid, false); if (unlikely(!backbone_gw)) return 1; /* handle as ANNOUNCE frame */ backbone_gw->lasttime = jiffies; crc = ntohs(*((__be16 *)(&an_addr[4]))); batadv_dbg(BATADV_DBG_BLA, bat_priv, "handle_announce(): ANNOUNCE vid %d (sent by %pM)... CRC = %#.4x\n", BATADV_PRINT_VID(vid), backbone_gw->orig, crc); if (backbone_gw->crc != crc) { batadv_dbg(BATADV_DBG_BLA, backbone_gw->bat_priv, "handle_announce(): CRC FAILED for %pM/%d (my = %#.4x, sent = %#.4x)\n", backbone_gw->orig, BATADV_PRINT_VID(backbone_gw->vid), backbone_gw->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_free_ref(backbone_gw); 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 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, "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); batadv_bla_del_backbone_claims(backbone_gw); hlist_del_rcu(&backbone_gw->hash_entry); batadv_backbone_gw_free_ref(backbone_gw); } spin_unlock_bh(list_lock); } }
/* @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 batadv_bla_answer_request(struct batadv_priv *bat_priv, struct batadv_hard_iface *primary_if, short vid) { struct hlist_node *node; struct hlist_head *head; struct batadv_hashtable *hash; struct batadv_claim *claim; struct batadv_backbone_gw *backbone_gw; int i; batadv_dbg(BATADV_DBG_BLA, bat_priv, "bla_answer_request(): received a claim request, send all of our own claims again\n"); 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, node, 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_free_ref(backbone_gw); }
/** * batadv_bla_is_backbone_gw * @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 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 0; /* first, find out the vid. */ if (!pskb_may_pull(skb, hdr_size + ETH_HLEN)) return 0; 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 0; batadv_backbone_gw_free_ref(backbone_gw); return 1; }
/* finally deinitialize the claim */ static void batadv_claim_release(struct batadv_bla_claim *claim) { batadv_backbone_gw_free_ref(claim->backbone_gw); kfree_rcu(claim, rcu); }