diff options
Diffstat (limited to 'net/batman-adv/hard-interface.c')
| -rw-r--r-- | net/batman-adv/hard-interface.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index 08ce36147c4c..a7a462e6fee5 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -228,6 +228,58 @@ bool batadv_is_wifi_netdev(struct net_device *net_device) return false; } +/** + * batadv_hardif_no_broadcast - check whether (re)broadcast is necessary + * @if_outgoing: the outgoing interface checked and considered for (re)broadcast + * @orig_addr: the originator of this packet + * @orig_neigh: originator address of the forwarder we just got the packet from + * (NULL if we originated) + * + * Checks whether a packet needs to be (re)broadcasted on the given interface. + * + * Return: + * BATADV_HARDIF_BCAST_NORECIPIENT: No neighbor on interface + * BATADV_HARDIF_BCAST_DUPFWD: Just one neighbor, but it is the forwarder + * BATADV_HARDIF_BCAST_DUPORIG: Just one neighbor, but it is the originator + * BATADV_HARDIF_BCAST_OK: Several neighbors, must broadcast + */ +int batadv_hardif_no_broadcast(struct batadv_hard_iface *if_outgoing, + u8 *orig_addr, u8 *orig_neigh) +{ + struct batadv_hardif_neigh_node *hardif_neigh; + struct hlist_node *first; + int ret = BATADV_HARDIF_BCAST_OK; + + rcu_read_lock(); + + /* 0 neighbors -> no (re)broadcast */ + first = rcu_dereference(hlist_first_rcu(&if_outgoing->neigh_list)); + if (!first) { + ret = BATADV_HARDIF_BCAST_NORECIPIENT; + goto out; + } + + /* >1 neighbors -> (re)brodcast */ + if (rcu_dereference(hlist_next_rcu(first))) + goto out; + + hardif_neigh = hlist_entry(first, struct batadv_hardif_neigh_node, + list); + + /* 1 neighbor, is the originator -> no rebroadcast */ + if (orig_addr && batadv_compare_eth(hardif_neigh->orig, orig_addr)) { + ret = BATADV_HARDIF_BCAST_DUPORIG; + /* 1 neighbor, is the one we received from -> no rebroadcast */ + } else if (orig_neigh && + batadv_compare_eth(hardif_neigh->orig, orig_neigh)) { + ret = BATADV_HARDIF_BCAST_DUPFWD; + } + +out: + rcu_read_unlock(); + return ret; +} + static struct batadv_hard_iface * batadv_hardif_get_active(const struct net_device *soft_iface) { |