/* Copyright (C) 2007-2013 B.A.T.M.A.N. contributors: * * Marek Lindner, Simon Wunderlich * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA */ #include "main.h" #include "translation-table.h" #include "originator.h" #include "routing.h" #include "gateway_common.h" #include "gateway_client.h" #include "hard-interface.h" #include "send.h" #include "bat_algo.h" #include "network-coding.h" /** * batadv_ring_buffer_set - update the ring buffer with the given value * @lq_recv: pointer to the ring buffer * @lq_index: index to store the value at * @value: value to store in the ring buffer */ static void batadv_ring_buffer_set(uint8_t lq_recv[], uint8_t *lq_index, uint8_t value) { lq_recv[*lq_index] = value; *lq_index = (*lq_index + 1) % BATADV_TQ_GLOBAL_WINDOW_SIZE; } /** * batadv_ring_buffer_set - compute the average of all non-zero values stored * in the given ring buffer * @lq_recv: pointer to the ring buffer * * Returns computed average value. */ static uint8_t batadv_ring_buffer_avg(const uint8_t lq_recv[]) { const uint8_t *ptr; uint16_t count = 0, i = 0, sum = 0; ptr = lq_recv; while (i < BATADV_TQ_GLOBAL_WINDOW_SIZE) { if (*ptr != 0) { count++; sum += *ptr; } i++; ptr++; } if (count == 0) return 0; return (uint8_t)(sum / count); } static struct batadv_neigh_node * batadv_iv_ogm_neigh_new(struct batadv_hard_iface *hard_iface, const uint8_t *neigh_addr, struct batadv_orig_node *orig_node, struct batadv_orig_node *orig_neigh) { struct batadv_neigh_node *neigh_node; neigh_node = batadv_neigh_node_new(hard_iface, neigh_addr); if (!neigh_node) goto out; INIT_LIST_HEAD(&neigh_node->bonding_list); neigh_node->orig_node = orig_neigh; neigh_node->if_incoming = hard_iface; spin_lock_bh(&orig_node->neigh_list_lock); hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list); spin_unlock_bh(&orig_node->neigh_list_lock); out: return neigh_node; } static int batadv_iv_ogm_iface_enable(struct batadv_hard_iface *hard_iface) { struct batadv_ogm_packet *batadv_ogm_packet; unsigned char *ogm_buff; uint32_t random_seqno; int res = -ENOMEM; /* randomize initial seqno to avoid collision */ get_random_bytes(&random_seqno, sizeof(random_seqno)); atomic_set(&hard_iface->bat_iv.ogm_seqno, random_seqno); hard_iface->bat_iv.ogm_buff_len = BATADV_OGM_HLEN; ogm_buff = kmalloc(hard_iface->bat_iv.ogm_buff_len, GFP_ATOMIC); if (!ogm_buff) goto out; hard_iface->bat_iv.ogm_buff = ogm_buff; batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff; batadv_ogm_packet->header.packet_type = BATADV_IV_OGM; batadv_ogm_packet->header.version = BATADV_COMPAT_VERSION; batadv_ogm_packet->header.ttl = 2; batadv_ogm_packet->flags = BATADV_NO_FLAGS; batadv_ogm_packet->tq = BATADV_TQ_MAX_VALUE; batadv_ogm_packet->tt_num_changes = 0; batadv_ogm_packet->ttvn = 0; res = 0; out: return res; } static void batadv_iv_ogm_iface_disable(struct batadv_hard_iface *hard_iface) { kfree(hard_iface->bat_iv.ogm_buff); hard_iface->bat_iv.ogm_buff = NULL; } static void batadv_iv_ogm_iface_update_mac(struct batadv_hard_iface *hard_iface) { struct batadv_ogm_packet *batadv_ogm_packet; unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff; batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff; memcpy(batadv_ogm_packet->orig, hard_iface->net_dev->dev_addr, ETH_ALEN); memcpy(batadv_ogm_packet->prev_sender, hard_iface->net_dev->dev_addr, ETH_ALEN); } static void batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface) { struct batadv_ogm_packet *batadv_ogm_packet; unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff; batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff; batadv_ogm_packet->flags = BATADV_PRIMARIES_FIRST_HOP; batadv_ogm_packet->header.ttl = BATADV_TTL; } /* when do we schedule our own ogm to be sent */ static unsigned long batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv) { unsigned int msecs; msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER; msecs += prandom_u32() % (2 * BATADV_JITTER); return jiffies + msecs_to_jiffies(msecs); } /* when do we schedule a ogm packet to be sent */ static unsigned long batadv_iv_ogm_fwd_send_time(void) { return jiffies + msecs_to_jiffies(prandom_u32() % (BATADV_JITTER / 2)); } /* apply hop penalty for a normal link */ static uint8_t batadv_hop_penalty(uint8_t tq, const struct batadv_priv *bat_priv) { int hop_penalty = atomic_read(&bat_priv->hop_penalty); int new_tq; new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty); new_tq /= BATADV_TQ_MAX_VALUE; return new_tq; } /* is there another aggregated packet here? */ static int batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len, int tt_num_changes) { int next_buff_pos = 0; next_buff_pos += buff_pos + BATADV_OGM_HLEN; next_buff_pos += batadv_tt_len(tt_num_changes); return (next_buff_pos <= packet_len) && (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES); } /* send a batman ogm to a given interface */ static void batadv_iv_ogm_send_to_if(struct batadv_forw_packet *forw_packet, struct batadv_hard_iface *hard_iface) { struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); char *fwd_str; uint8_t packet_num; int16_t buff_pos; struct batadv_ogm_packet *batadv_ogm_packet; struct sk_buff *skb; uint8_t *packet_pos; if (hard_iface->if_status != BATADV_IF_ACTIVE) return; packet_num = 0; buff_pos = 0; packet_pos = forw_packet->skb->data; batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos; /* adjust all flags and log packets */ while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len, batadv_ogm_packet->tt_num_changes)) { /* we might have aggregated direct link packets with an * ordinary base packet */ if (forw_packet->direct_link_flags & BIT(packet_num) && forw_packet->if_incoming == hard_iface) batadv_ogm_packet->flags |= BATADV_DIRECTLINK; else batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK; if (packet_num > 0 || !forw_packet->own) fwd_str = "Forwarding"; else fwd_str = "Sending own"; batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s, ttvn %d) on interface %s [%pM]\n", fwd_str, (packet_num > 0 ? "aggregated " : ""), batadv_ogm_packet->orig, ntohl(batadv_ogm_packet->seqno), batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl, (batadv_ogm_packet->flags & BATADV_DIRECTLINK ? "on" : "off"), batadv_ogm_packet->ttvn, hard_iface->net_dev->name, hard_iface->net_dev->dev_addr); buff_pos += BATADV_OGM_HLEN; buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes); packet_num++; packet_pos = forw_packet->skb->data + buff_pos; batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos; } /* create clone because function is called more than once */ skb = skb_clone(forw_packet->skb, GFP_ATOMIC); if (skb) { batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX); batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES, skb->len + ETH_HLEN); batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr); } } /* send a batman ogm packet */ static void batadv_iv_ogm_emit(struct batadv_forw_packet *forw_packet) { struct batadv_hard_iface *hard_iface; struct net_device *soft_iface; struct batadv_priv *bat_priv; struct batadv_hard_iface *primary_if = NULL; struct batadv_ogm_packet *batadv_ogm_packet; unsigned char directlink; uint8_t *packet_pos; packet_pos = forw_packet->skb->data; batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos; directlink = (batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0); if (!forw_packet->if_incoming) { pr_err("Error - can't forward packet: incoming iface not specified\n"); goto out; } soft_iface = forw_packet->if_incoming->soft_iface; bat_priv = netdev_priv(soft_iface); if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE) goto out; primary_if = batadv_primary_if_get_selected(bat_priv); if (!primary_if) goto out; /* multihomed peer assumed * non-primary OGMs are only broadcasted on their interface */ if ((directlink && (batadv_ogm_packet->header.ttl == 1)) || (forw_packet->own && (forw_packet->if_incoming != primary_if))) { /* FIXME: what about aggregated packets ? */ batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n", (forw_packet->own ? "Sending own" : "Forwarding"), batadv_ogm_packet->orig, ntohl(batadv_ogm_packet->seqno), batadv_ogm_packet->header.ttl, forw_packet->if_incoming->net_dev->name, forw_packet->if_incoming->net_dev->dev_addr); /* skb is only used once and than forw_packet is free'd */ batadv_send_skb_packet(forw_packet->skb, forw_packet->if_incoming, batadv_broadcast_addr); forw_packet->skb = NULL; goto out; } /* broadcast on every interface */ rcu_read_lock(); list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { if (hard_iface->soft_iface != soft_iface) continue; batadv_iv_ogm_send_to_if(forw_packet, hard_iface); } rcu_read_unlock(); out: if (primary_if) batadv_hardif_free_ref(primary_if); } /* return true if new_packet can be aggregated with forw_packet */ static bool batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet, struct batadv_priv *bat_priv, int packet_len, unsigned long send_time, bool directlink, const struct batadv_hard_iface *if_incoming, const struct batadv_forw_packet *forw_packet) { struct batadv_ogm_packet *batadv_ogm_packet; int aggregated_bytes = forw_packet->packet_len + packet_len; struct batadv_hard_iface *primary_if = NULL; bool res = false; unsigned long aggregation_end_time; batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data; aggregation_end_time = send_time; aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS); /* we can aggregate the current packet to this aggregated packet * if: * * - the send time is within our MAX_AGGREGATION_MS time * - the resulting packet wont be bigger than * MAX_AGGREGATION_BYTES */ if (time_before(send_time, forw_packet->send_time) && time_after_eq(aggregation_end_time, forw_packet->send_time) && (aggregated_bytes <= BATADV_MAX_AGGREGATION_BYTES)) { /* check aggregation compatibility * -> direct link packets are broadcasted on * their interface only * -> aggregate packet if the current packet is * a "global" packet as well as the base * packet */ primary_if = batadv_primary_if_get_selected(bat_priv); if (!primary_if) goto out; /* packets without direct link flag and high TTL * are flooded through the net */ if ((!directlink) && (!(batadv_ogm_packet->flags & BATADV_DIRECTLINK)) && (batadv_ogm_packet->header.ttl != 1) && /* own packets originating non-primary * interfaces leave only that interface */ ((!forw_packet->own) || (forw_packet->if_incoming == primary_if))) { res = true; goto out; } /* if the incoming packet is sent via this one * interface only - we still can aggregate */ if ((directlink) && (new_bat_ogm_packet->header.ttl == 1) && (forw_packet->if_incoming == if_incoming) && /* packets from direct neighbors or * own secondary interface packets * (= secondary interface packets in general) */ (batadv_ogm_packet->flags & BATADV_DIRECTLINK || (forw_packet->own && forw_packet->if_incoming != primary_if))) { res = true; goto out; } } out: if (primary_if) batadv_hardif_free_ref(primary_if); return res; } /* create a new aggregated packet and add this packet to it */ static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff, int packet_len, unsigned long send_time, bool direct_link, struct batadv_hard_iface *if_incoming, int own_packet) { struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface); struct batadv_forw_packet *forw_packet_aggr; unsigned char *skb_buff; unsigned int skb_size; if (!atomic_inc_not_zero(&if_incoming->refcount)) return; /* own packet should always be scheduled */ if (!own_packet) { if (!batadv_atomic_dec_not_zero(&bat_priv->batman_queue_left)) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "batman packet queue full\n"); goto out; } } forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC); if (!forw_packet_aggr) { if (!own_packet) atomic_inc(&bat_priv->batman_queue_left); goto out; } if ((atomic_read(&bat_priv->aggregated_ogms)) && (packet_len < BATADV_MAX_AGGREGATION_BYTES)) skb_size = BATADV_MAX_AGGREGATION_BYTES; else skb_size = packet_len; skb_size += ETH_HLEN + NET_IP_ALIGN; forw_packet_aggr->skb = dev_alloc_skb(skb_size); if (!forw_packet_aggr->skb) { if (!own_packet) atomic_inc(&bat_priv->batman_queue_left); kfree(forw_packet_aggr); goto out; } skb_reserve(forw_packet_aggr->skb, ETH_HLEN + NET_IP_ALIGN); INIT_HLIST_NODE(&forw_packet_aggr->list); skb_buff = skb_put(forw_packet_aggr->skb, packet_len); forw_packet_aggr->packet_len = packet_len; memcpy(skb_buff, packet_buff, packet_len); forw_packet_aggr->own = own_packet; forw_packet_aggr->if_incoming = if_incoming; forw_packet_aggr->num_packets = 0; forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS; forw_packet_aggr->send_time = send_time; /* save packet direct link flag status */ if (direct_link) forw_packet_aggr->direct_link_flags |= 1; /* add new packet to packet list */ spin_lock_bh(&bat_priv->forw_bat_list_lock); hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list); spin_unlock_bh(&bat_priv->forw_bat_list_lock); /* start timer for this packet */ INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work, batadv_send_outstanding_bat_ogm_packet); queue_delayed_work(batadv_event_workqueue, &forw_packet_aggr->delayed_work, send_time - jiffies); return; out: batadv_hardif_free_ref(if_incoming); } /* aggregate a new packet into the existing ogm packet */ static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr, const unsigned char *packet_buff, int packet_len, bool direct_link) { unsigned char *skb_buff; unsigned long new_direct_link_flag; skb_buff = skb_put(forw_packet_aggr->skb, packet_len); memcpy(skb_buff, packet_buff, packet_len); forw_packet_aggr->packet_len += packet_len; forw_packet_aggr->num_packets++; /* save packet direct link flag status */ if (direct_link) { new_direct_link_flag = BIT(forw_packet_aggr->num_packets); forw_packet_aggr->direct_link_flags |= new_direct_link_flag; } } static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv, unsigned char *packet_buff, int packet_len, struct batadv_hard_iface *if_incoming, int own_packet, unsigned long send_time) { /* _aggr -> pointer to the packet we want to aggregate with * _pos -> pointer to the position in the queue */ struct batadv_forw_packet *forw_packet_aggr = NULL; struct batadv_forw_packet *forw_packet_pos = NULL; struct batadv_ogm_packet *batadv_ogm_packet; bool direct_link; unsigned long max_aggregation_jiffies; batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff; direct_link = batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0; max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS); /* find position for the packet in the forward queue */ spin_lock_bh(&bat_priv->forw_bat_list_lock); /* own packets are not to be aggregated */ if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) { hlist_for_each_entry(forw_packet_pos, &bat_priv->forw_bat_list, list) { if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet, bat_priv, packet_len, send_time, direct_link, if_incoming, forw_packet_pos)) { forw_packet_aggr = forw_packet_pos; break; } } } /* nothing to aggregate with - either aggregation disabled or no * suitable aggregation packet found */ if (!forw_packet_aggr) { /* the following section can run without the lock */ spin_unlock_bh(&bat_priv->forw_bat_list_lock); /* if we could not aggregate this packet with one of the others * we hold it back for a while, so that it might be aggregated * later on */ if (!own_packet && atomic_read(&bat_priv->aggregated_ogms)) send_time += max_aggregation_jiffies; batadv_iv_ogm_aggregate_new(packet_buff, packet_len, send_time, direct_link, if_incoming, own_packet); } else { batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff, packet_len, direct_link); spin_unlock_bh(&bat_priv->forw_bat_list_lock); } } static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node, const struct ethhdr *ethhdr, struct batadv_ogm_packet *batadv_ogm_packet, bool is_single_hop_neigh, bool is_from_best_next_hop, struct batadv_hard_iface *if_incoming) { struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface); uint8_t tt_num_changes; if (batadv_ogm_packet->header.ttl <= 1) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n"); return; } if (!is_from_best_next_hop) { /* Mark the forwarded packet when it is not coming from our * best next hop. We still need to forward the packet for our * neighbor link quality detection to work in case the packet * originated from a single hop neighbor. Otherwise we can * simply drop the ogm. */ if (is_single_hop_neigh) batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP; else return; } tt_num_changes = batadv_ogm_packet->tt_num_changes; batadv_ogm_packet->header.ttl--; memcpy(batadv_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN); /* apply hop penalty */ batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq, bat_priv); batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Forwarding packet: tq: %i, ttl: %i\n", batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl); /* switch of primaries first hop flag when forwarding */ batadv_ogm_packet->flags &= ~BATADV_PRIMARIES_FIRST_HOP; if (is_single_hop_neigh) batadv_ogm_packet->flags |= BATADV_DIRECTLINK; else batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK; batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet, BATADV_OGM_HLEN + batadv_tt_len(tt_num_changes), if_incoming, 0, batadv_iv_ogm_fwd_send_time()); } static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface) { struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); unsigned char **ogm_buff = &hard_iface->bat_iv.ogm_buff; struct batadv_ogm_packet *batadv_ogm_packet; struct batadv_hard_iface *primary_if; int *ogm_buff_len = &hard_iface->bat_iv.ogm_buff_len; int vis_server, tt_num_changes = 0; uint32_t seqno; uint8_t bandwidth; vis_server = atomic_read(&bat_priv->vis_mode); primary_if = batadv_primary_if_get_selected(bat_priv); if (hard_iface == primary_if) tt_num_changes = batadv_tt_append_diff(bat_priv, ogm_buff, ogm_buff_len, BATADV_OGM_HLEN); batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff); /* change sequence number to network order */ seqno = (uint32_t)atomic_read(&hard_iface->bat_iv.ogm_seqno); batadv_ogm_packet->seqno = htonl(seqno); atomic_inc(&hard_iface->bat_iv.ogm_seqno); batadv_ogm_packet->ttvn = atomic_read(&bat_priv->tt.vn); batadv_ogm_packet->tt_crc = htons(bat_priv->tt.local_crc); if (tt_num_changes >= 0) batadv_ogm_packet->tt_num_changes = tt_num_changes; if (vis_server == BATADV_VIS_TYPE_SERVER_SYNC) batadv_ogm_packet->flags |= BATADV_VIS_SERVER; else batadv_ogm_packet->flags &= ~BATADV_VIS_SERVER; if (hard_iface == primary_if && atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_SERVER) { bandwidth = (uint8_t)atomic_read(&bat_priv->gw_bandwidth); batadv_ogm_packet->gw_flags = bandwidth; } else { batadv_ogm_packet->gw_flags = BATADV_NO_FLAGS; } batadv_slide_own_bcast_window(hard_iface); batadv_iv_ogm_queue_add(bat_priv, hard_iface->bat_iv.ogm_buff, hard_iface->bat_iv.ogm_buff_len, hard_iface, 1, batadv_iv_ogm_emit_send_time(bat_priv)); if (primary_if) batadv_hardif_free_ref(primary_if); } static void batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv, struct batadv_orig_node *orig_node, const struct ethhdr *ethhdr, const struct batadv_ogm_packet *batadv_ogm_packet, struct batadv_hard_iface *if_incoming, const unsigned char *tt_buff, int is_duplicate) { struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL; struct batadv_neigh_node *router = NULL; struct batadv_orig_node *orig_node_tmp; int if_num; uint8_t sum_orig, sum_neigh; uint8_t *neigh_addr; uint8_t tq_avg; batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "update_originator(): Searching and updating originator entry of received packet\n"); rcu_read_lock(); hlist_for_each_entry_rcu(tmp_neigh_node, &orig_node->neigh_list, list) { neigh_addr = tmp_neigh_node->addr; if (batadv_compare_eth(neigh_addr, ethhdr->h_source) && tmp_neigh_node->if_incoming == if_incoming && atomic_inc_not_zero(&tmp_neigh_node->refcount)) { if (WARN(neigh_node, "too many matching neigh_nodes")) batadv_neigh_node_free_ref(neigh_node); neigh_node = tmp_neigh_node; continue; } if (is_duplicate) continue; spin_lock_bh(&tmp_neigh_node->lq_update_lock); batadv_ring_buffer_set(tmp_neigh_node->tq_recv, &tmp_neigh_node->tq_index, 0); tq_avg = batadv_ring_buffer_avg(tmp_neigh_node->tq_recv); tmp_neigh_node->tq_avg = tq_avg; spin_unlock_bh(&tmp_neigh_node->lq_update_lock); } if (!neigh_node) { struct batadv_orig_node *orig_tmp; orig_tmp = batadv_get_orig_node(bat_priv, ethhdr->h_source); if (!orig_tmp) goto unlock; neigh_node = batadv_iv_ogm_neigh_new(if_incoming, ethhdr->h_source, orig_node, orig_tmp); batadv_orig_node_free_ref(orig_tmp); if (!neigh_node) goto unlock; } else batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Updating existing last-hop neighbor of originator\n"); rcu_read_unlock(); orig_node->flags = batadv_ogm_packet->flags; neigh_node->last_seen = jiffies; spin_lock_bh(&neigh_node->lq_update_lock); batadv_ring_buffer_set(neigh_node->tq_recv, &neigh_node->tq_index, batadv_ogm_packet->tq); neigh_node->tq_avg = batadv_ring_buffer_avg(neigh_node->tq_recv); spin_unlock_bh(&neigh_node->lq_update_lock); if (!is_duplicate) { orig_node->last_ttl = batadv_ogm_packet->header.ttl; neigh_node->last_ttl = batadv_ogm_packet->header.ttl; } batadv_bonding_candidate_add(orig_node, neigh_node); /* if this neighbor already is our next hop there is nothing * to change */ router = batadv_orig_node_get_router(orig_node); if (router == neigh_node) goto update_tt; /* if this neighbor does not offer a better TQ we won't consider it */ if (router && (router->tq_avg > neigh_node->tq_avg)) goto update_tt; /* if the TQ is the same and the link not more symmetric we * won't consider it either */ if (router && (neigh_node->tq_avg == router->tq_avg)) { orig_node_tmp = router->orig_node; spin_lock_bh(&orig_node_tmp->ogm_cnt_lock); if_num = router->if_incoming->if_num; sum_orig = orig_node_tmp->bcast_own_sum[if_num]; spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock); orig_node_tmp = neigh_node->orig_node; spin_lock_bh(&orig_node_tmp->ogm_cnt_lock); if_num = neigh_node->if_incoming->if_num; sum_neigh = orig_node_tmp->bcast_own_sum[if_num]; spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock); if (sum_orig >= sum_neigh) goto update_tt; } batadv_update_route(bat_priv, orig_node, neigh_node); update_tt: /* I have to check for transtable changes only if the OGM has been * sent through a primary interface */ if (((batadv_ogm_packet->orig != ethhdr->h_source) && (batadv_ogm_packet->header.ttl > 2)) || (batadv_ogm_packet->flags & BATADV_PRIMARIES_FIRST_HOP)) batadv_tt_update_orig(bat_priv, orig_node, tt_buff, batadv_ogm_packet->tt_num_changes, batadv_ogm_packet->ttvn, ntohs(batadv_ogm_packet->tt_crc)); if (orig_node->gw_flags != batadv_ogm_packet->gw_flags) batadv_gw_node_update(bat_priv, orig_node, batadv_ogm_packet->gw_flags); orig_node->gw_flags = batadv_ogm_packet->gw_flags; /* restart gateway selection if fast or late switching was enabled */ if ((orig_node->gw_flags) && (atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_CLIENT) && (atomic_read(&bat_priv->gw_sel_class) > 2)) batadv_gw_check_election(bat_priv, orig_node); goto out; unlock: rcu_read_unlock(); out: if (neigh_node) batadv_neigh_node_free_ref(neigh_node); if (router) batadv_neigh_node_free_ref(router); } static int batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node, struct batadv_orig_node *orig_neigh_node, struct batadv_ogm_packet *batadv_ogm_packet, struct batadv_hard_iface *if_incoming) { struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface); struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node; uint8_t total_count; uint8_t orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own; unsigned int neigh_rq_inv_cube, neigh_rq_max_cube; int tq_asym_penalty, inv_asym_penalty, ret = 0; unsigned int combined_tq; /* find corresponding one hop neighbor */ rcu_read_lock(); hlist_for_each_entry_rcu(tmp_neigh_node, &orig_neigh_node->neigh_list, list) { if (!batadv_compare_eth(tmp_neigh_node->addr, orig_neigh_node->orig)) continue; if (tmp_neigh_node->if_incoming != if_incoming) continue; if (!atomic_inc_not_zero(&tmp_neigh_node->refcount)) continue; neigh_node = tmp_neigh_node; break; } rcu_read_unlock(); if (!neigh_node) neigh_node = batadv_iv_ogm_neigh_new(if_incoming, orig_neigh_node->orig, orig_neigh_node, orig_neigh_node); if (!neigh_node) goto out; /* if orig_node is direct neighbor update neigh_node last_seen */ if (orig_node == orig_neigh_node) neigh_node->last_seen = jiffies; orig_node->last_seen = jiffies; /* find packet count of corresponding one hop neighbor */ spin_lock_bh(&orig_node->ogm_cnt_lock); orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num]; neigh_rq_count = neigh_node->real_packet_count; spin_unlock_bh(&orig_node->ogm_cnt_lock); /* pay attention to not get a value bigger than 100 % */ if (orig_eq_count > neigh_rq_count) total_count = neigh_rq_count; else total_count = orig_eq_count; /* if we have too few packets (too less data) we set tq_own to zero * if we receive too few packets it is not considered bidirectional */ if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM || neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM) tq_own = 0; else /* neigh_node->real_packet_count is never zero as we * only purge old information when getting new * information */ tq_own = (BATADV_TQ_MAX_VALUE * total_count) / neigh_rq_count; /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does * affect the nearly-symmetric links only a little, but * punishes asymmetric links more. This will give a value * between 0 and TQ_MAX_VALUE */ neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count; neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv; neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE * BATADV_TQ_LOCAL_WINDOW_SIZE * BATADV_TQ_LOCAL_WINDOW_SIZE; inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube; inv_asym_penalty /= neigh_rq_max_cube; tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty; combined_tq = batadv_ogm_packet->tq * tq_own * tq_asym_penalty; combined_tq /= BATADV_TQ_MAX_VALUE * BATADV_TQ_MAX_VALUE; batadv_ogm_packet->tq = combined_tq; batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n", orig_node->orig, orig_neigh_node->orig, total_count, neigh_rq_count, tq_own, tq_asym_penalty, batadv_ogm_packet->tq); /* if link has the minimum required transmission quality * consider it bidirectional */ if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT) ret = 1; out: if (neigh_node) batadv_neigh_node_free_ref(neigh_node); return ret; } /* processes a batman packet for all interfaces, adjusts the sequence number and * finds out whether it is a duplicate. * returns: * 1 the packet is a duplicate * 0 the packet has not yet been received * -1 the packet is old and has been received while the seqno window * was protected. Caller should drop it. */ static int batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr, const struct batadv_ogm_packet *batadv_ogm_packet, const struct batadv_hard_iface *if_incoming) { struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface); struct batadv_orig_node *orig_node; struct batadv_neigh_node *tmp_neigh_node; int is_duplicate = 0; int32_t seq_diff; int need_update = 0; int set_mark, ret = -1; uint32_t seqno = ntohl(batadv_ogm_packet->seqno); uint8_t *neigh_addr; uint8_t packet_count; orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig); if (!orig_node) return 0; spin_lock_bh(&orig_node->ogm_cnt_lock); seq_diff = seqno - orig_node->last_real_seqno; /* signalize caller that the packet is to be dropped. */ if (!hlist_empty(&orig_node->neigh_list) && batadv_window_protected(bat_priv, seq_diff, &orig_node->batman_seqno_reset)) goto out; rcu_read_lock(); hlist_for_each_entry_rcu(tmp_neigh_node, &orig_node->neigh_list, list) { is_duplicate |= batadv_test_bit(tmp_neigh_node->real_bits, orig_node->last_real_seqno, seqno); neigh_addr = tmp_neigh_node->addr; if (batadv_compare_eth(neigh_addr, ethhdr->h_source) && tmp_neigh_node->if_incoming == if_incoming) set_mark = 1; else set_mark = 0; /* if the window moved, set the update flag. */ need_update |= batadv_bit_get_packet(bat_priv, tmp_neigh_node->real_bits, seq_diff, set_mark); packet_count = bitmap_weight(tmp_neigh_node->real_bits, BATADV_TQ_LOCAL_WINDOW_SIZE); tmp_neigh_node->real_packet_count = packet_count; } rcu_read_unlock(); if (need_update) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "updating last_seqno: old %u, new %u\n", orig_node->last_real_seqno, seqno); orig_node->last_real_seqno = seqno; } ret = is_duplicate; out: spin_unlock_bh(&orig_node->ogm_cnt_lock); batadv_orig_node_free_ref(orig_node); return ret; } static void batadv_iv_ogm_process(const struct ethhdr *ethhdr, struct batadv_ogm_packet *batadv_ogm_packet, const unsigned char *tt_buff, struct batadv_hard_iface *if_incoming) { struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface); struct batadv_hard_iface *hard_iface; struct batadv_orig_node *orig_neigh_node, *orig_node; struct batadv_neigh_node *router = NULL, *router_router = NULL; struct batadv_neigh_node *orig_neigh_router = NULL; int has_directlink_flag; int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0; int is_bidirect; bool is_single_hop_neigh = false; bool is_from_best_next_hop = false; int is_duplicate, sameseq, simlar_ttl; uint32_t if_incoming_seqno; uint8_t *prev_sender; /* Silently drop when the batman packet is actually not a * correct packet. * * This might happen if a packet is padded (e.g. Ethernet has a * minimum frame length of 64 byte) and the aggregation interprets * it as an additional length. * * TODO: A more sane solution would be to have a bit in the * batadv_ogm_packet to detect whether the packet is the last * packet in an aggregation. Here we expect that the padding * is always zero (or not 0x01) */ if (batadv_ogm_packet->header.packet_type != BATADV_IV_OGM) return; /* could be changed by schedule_own_packet() */ if_incoming_seqno = atomic_read(&if_incoming->bat_iv.ogm_seqno); if (batadv_ogm_packet->flags & BATADV_DIRECTLINK) has_directlink_flag = 1; else has_directlink_flag = 0; if (batadv_compare_eth(ethhdr->h_source, batadv_ogm_packet->orig)) is_single_hop_neigh = true; batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Received BATMAN packet via NB: %pM, IF: %s [%pM] (from OG: %pM, via prev OG: %pM, seqno %u, ttvn %u, crc %#.4x, changes %u, tq %d, TTL %d, V %d, IDF %d)\n", ethhdr->h_source, if_incoming->net_dev->name, if_incoming->net_dev->dev_addr, batadv_ogm_packet->orig, batadv_ogm_packet->prev_sender, ntohl(batadv_ogm_packet->seqno), batadv_ogm_packet->ttvn, ntohs(batadv_ogm_packet->tt_crc), batadv_ogm_packet->tt_num_changes, batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl, batadv_ogm_packet->header.version, has_directlink_flag); rcu_read_lock(); list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { if (hard_iface->if_status != BATADV_IF_ACTIVE) continue; if (hard_iface->soft_iface != if_incoming->soft_iface) continue; if (batadv_compare_eth(ethhdr->h_source, hard_iface->net_dev->dev_addr)) is_my_addr = 1; if (batadv_compare_eth(batadv_ogm_packet->orig, hard_iface->net_dev->dev_addr)) is_my_orig = 1; if (batadv_compare_eth(batadv_ogm_packet->prev_sender, hard_iface->net_dev->dev_addr)) is_my_oldorig = 1; } rcu_read_unlock(); if (is_my_addr) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Drop packet: received my own broadcast (sender: %pM)\n", ethhdr->h_source); return; } if (is_my_orig) { unsigned long *word; int offset; int32_t bit_pos; int16_t if_num; uint8_t *weight; orig_neigh_node = batadv_get_orig_node(bat_priv, ethhdr->h_source); if (!orig_neigh_node) return; /* neighbor has to indicate direct link and it has to * come via the corresponding interface * save packet seqno for bidirectional check */ if (has_directlink_flag && batadv_compare_eth(if_incoming->net_dev->dev_addr, batadv_ogm_packet->orig)) { if_num = if_incoming->if_num; offset = if_num * BATADV_NUM_WORDS; spin_lock_bh(&orig_neigh_node->ogm_cnt_lock); word = &(orig_neigh_node->bcast_own[offset]); bit_pos = if_incoming_seqno - 2; bit_pos -= ntohl(batadv_ogm_packet->seqno); batadv_set_bit(word, bit_pos); weight = &orig_neigh_node->bcast_own_sum[if_num]; *weight = bitmap_weight(word, BATADV_TQ_LOCAL_WINDOW_SIZE); spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock); } batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Drop packet: originator packet from myself (via neighbor)\n"); batadv_orig_node_free_ref(orig_neigh_node); return; } if (is_my_oldorig) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n", ethhdr->h_source); return; } if (batadv_ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n", ethhdr->h_source); return; } orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig); if (!orig_node) return; is_duplicate = batadv_iv_ogm_update_seqnos(ethhdr, batadv_ogm_packet, if_incoming); if (is_duplicate == -1) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Drop packet: packet within seqno protection time (sender: %pM)\n", ethhdr->h_source); goto out; } if (batadv_ogm_packet->tq == 0) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Drop packet: originator packet with tq equal 0\n"); goto out; } router = batadv_orig_node_get_router(orig_node); if (router) router_router = batadv_orig_node_get_router(router->orig_node); if ((router && router->tq_avg != 0) && (batadv_compare_eth(router->addr, ethhdr->h_source))) is_from_best_next_hop = true; prev_sender = batadv_ogm_packet->prev_sender; /* avoid temporary routing loops */ if (router && router_router && (batadv_compare_eth(router->addr, prev_sender)) && !(batadv_compare_eth(batadv_ogm_packet->orig, prev_sender)) && (batadv_compare_eth(router->addr, router_router->addr))) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n", ethhdr->h_source); goto out; } /* if sender is a direct neighbor the sender mac equals * originator mac */ if (is_single_hop_neigh) orig_neigh_node = orig_node; else orig_neigh_node = batadv_get_orig_node(bat_priv, ethhdr->h_source); if (!orig_neigh_node) goto out; /* Update nc_nodes of the originator */ batadv_nc_update_nc_node(bat_priv, orig_node, orig_neigh_node, batadv_ogm_packet, is_single_hop_neigh); orig_neigh_router = batadv_orig_node_get_router(orig_neigh_node); /* drop packet if sender is not a direct neighbor and if we * don't route towards it */ if (!is_single_hop_neigh && (!orig_neigh_router)) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Drop packet: OGM via unknown neighbor!\n"); goto out_neigh; } is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node, batadv_ogm_packet, if_incoming); batadv_bonding_save_primary(orig_node, orig_neigh_node, batadv_ogm_packet); /* update ranking if it is not a duplicate or has the same * seqno and similar ttl as the non-duplicate */ sameseq = orig_node->last_real_seqno == ntohl(batadv_ogm_packet->seqno); simlar_ttl = orig_node->last_ttl - 3 <= batadv_ogm_packet->header.ttl; if (is_bidirect && (!is_duplicate || (sameseq && simlar_ttl))) batadv_iv_ogm_orig_update(bat_priv, orig_node, ethhdr, batadv_ogm_packet, if_incoming, tt_buff, is_duplicate); /* is single hop (direct) neighbor */ if (is_single_hop_neigh) { /* mark direct link on incoming interface */ batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet, is_single_hop_neigh, is_from_best_next_hop, if_incoming); batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Forwarding packet: rebroadcast neighbor packet with direct link flag\n"); goto out_neigh; } /* multihop originator */ if (!is_bidirect) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Drop packet: not received via bidirectional link\n"); goto out_neigh; } if (is_duplicate) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Drop packet: duplicate packet received\n"); goto out_neigh; } batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Forwarding packet: rebroadcast originator packet\n"); batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet, is_single_hop_neigh, is_from_best_next_hop, if_incoming); out_neigh: if ((orig_neigh_node) && (!is_single_hop_neigh)) batadv_orig_node_free_ref(orig_neigh_node); out: if (router) batadv_neigh_node_free_ref(router); if (router_router) batadv_neigh_node_free_ref(router_router); if (orig_neigh_router) batadv_neigh_node_free_ref(orig_neigh_router); batadv_orig_node_free_ref(orig_node); } static int batadv_iv_ogm_receive(struct sk_buff *skb, struct batadv_hard_iface *if_incoming) { struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface); struct batadv_ogm_packet *batadv_ogm_packet; struct ethhdr *ethhdr; int buff_pos = 0, packet_len; unsigned char *tt_buff, *packet_buff; bool ret; uint8_t *packet_pos; ret = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN); if (!ret) return NET_RX_DROP; /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface * that does not have B.A.T.M.A.N. IV enabled ? */ if (bat_priv->bat_algo_ops->bat_ogm_emit != batadv_iv_ogm_emit) return NET_RX_DROP; batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX); batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES, skb->len + ETH_HLEN); packet_len = skb_headlen(skb); ethhdr = eth_hdr(skb); packet_buff = skb->data; batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff; /* unpack the aggregated packets and process them one by one */ while (batadv_iv_ogm_aggr_packet(buff_pos, packet_len, batadv_ogm_packet->tt_num_changes)) { tt_buff = packet_buff + buff_pos + BATADV_OGM_HLEN; batadv_iv_ogm_process(ethhdr, batadv_ogm_packet, tt_buff, if_incoming); buff_pos += BATADV_OGM_HLEN; buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes); packet_pos = packet_buff + buff_pos; batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos; } kfree_skb(skb); return NET_RX_SUCCESS; } static struct batadv_algo_ops batadv_batman_iv __read_mostly = { .name = "BATMAN_IV", .bat_iface_enable = batadv_iv_ogm_iface_enable, .bat_iface_disable = batadv_iv_ogm_iface_disable, .bat_iface_update_mac = batadv_iv_ogm_iface_update_mac, .bat_primary_iface_set = batadv_iv_ogm_primary_iface_set, .bat_ogm_schedule = batadv_iv_ogm_schedule, .bat_ogm_emit = batadv_iv_ogm_emit, }; int __init batadv_iv_init(void) { int ret; /* batman originator packet */ ret = batadv_recv_handler_register(BATADV_IV_OGM, batadv_iv_ogm_receive); if (ret < 0) goto out; ret = batadv_algo_register(&batadv_batman_iv); if (ret < 0) goto handler_unregister; goto out; handler_unregister: batadv_recv_handler_unregister(BATADV_IV_OGM); out: return ret; }