We may only optimize the multicast packet flow, if an mcast_mode has been activated and if we are a multicast receiver of the same group. Otherwise flood the multicast packet without optimizations.
This allows us to still flood multicast packets of protocols where it is not easily possible for a multicast sender to be a multicast receiver of the same group instead of dropping them (for instance IPv6 NDP). This commit therefore also makes IPv6 usable again, if the proact_tracking multicast mode has been activated. Signed-off-by: Linus Lüssing <[email protected]> --- soft-interface.c | 28 ++++++++++++++++++++++++++-- 1 files changed, 26 insertions(+), 2 deletions(-) diff --git a/batman-adv/soft-interface.c b/batman-adv/soft-interface.c index 3e16522..c4b2f6f 100644 --- a/batman-adv/soft-interface.c +++ b/batman-adv/soft-interface.c @@ -340,6 +340,31 @@ static int interface_change_mtu(struct net_device *dev, int new_mtu) return 0; } +static int mcast_may_optimize(uint8_t *dest, struct net_device *soft_iface) +{ + struct netdev_hw_addr *mc_entry; + struct bat_priv *bat_priv = netdev_priv(soft_iface); + int mcast_mode = atomic_read(&bat_priv->mcast_mode); + + if (mcast_mode != MCAST_MODE_PROACT_TRACKING) + return 0; + + /* Still allow flooding of multicast packets of protocols where it is + * not easily possible for a multicast sender to be a multicast + * receiver of the same group (for instance IPv6 NDP) */ + netif_addr_lock_bh(soft_iface); + netdev_for_each_mc_addr(mc_entry, soft_iface) { + if (memcmp(dest, mc_entry->addr, ETH_ALEN)) + continue; + + netif_addr_unlock_bh(soft_iface); + return 1; + } + netif_addr_unlock_bh(soft_iface); + + return 0; +} + int interface_tx(struct sk_buff *skb, struct net_device *soft_iface) { struct ethhdr *ethhdr = (struct ethhdr *)skb->data; @@ -392,8 +417,7 @@ int interface_tx(struct sk_buff *skb, struct net_device *soft_iface) if (is_broadcast_ether_addr(ethhdr->h_dest)) bcast_dst = true; - else if (atomic_read(&bat_priv->mcast_mode) == - MCAST_MODE_PROACT_TRACKING) + else if (mcast_may_optimize(ethhdr->h_dest, soft_iface)) mcast_dst = true; else bcast_dst = true; -- 1.7.2.3
