On Monday, August 14, 2023 5:35:28 PM CEST Simon Wunderlich wrote:
I've read through that multiple times now, and I don't understand why next_dest isn't getting incremented within each iteration in the same way as dest. Is this a bug or am I missing something? Might be nicer to use one counter which is increased instead of two pointeres, e.g. &dest[counter] and &next_dest[counter] or similar to avoid those kind of bugs.
[...]
Discussed with Sven, next_dest is actually the iterator so it should be incremented at the other place.
I still think this is very hard to read, both Sven and I spent quite some time with pen and paper to understand this function. I would appreciate if it could be simplified.
+/**
- batadv_mcast_forw_tracker_tvlv_handler() - handle an mcast tracker
tvlv
- @bat_priv: the bat priv with all the soft interface information
- @skb: the received batman-adv multicast packet
- Parses the tracker TVLV of an incoming batman-adv multicast packet and
- forwards the packet as indicated in this TVLV.
- Caller needs to set the skb network header to the start of the
multicast + * tracker TVLV (excluding the generic TVLV header) and the skb transport header + * to the next byte after this multicast tracker TVLV.
- Caller needs to free the skb.
- Return: NET_RX_SUCCESS or NET_RX_DROP on success or a negative error
- code on failure. NET_RX_SUCCESS if the received packet is supposed to
be + * decapsulated and forwarded to the own soft interface, NET_RX_DROP otherwise. + */ +int batadv_mcast_forw_tracker_tvlv_handler(struct batadv_priv *bat_priv,
struct sk_buff *skb)+{
return batadv_mcast_forw_packet(bat_priv, skb, false);+} diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index 34903df4fe93..e46ce83c516a 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -942,6 +942,7 @@ struct batadv_orig_node *batadv_orig_node_new(struct batadv_priv *bat_priv, #ifdef CONFIG_BATMAN_ADV_MCAST orig_node->mcast_flags = BATADV_MCAST_WANT_NO_RTR4; orig_node->mcast_flags |= BATADV_MCAST_WANT_NO_RTR6;
orig_node->mcast_flags |= BATADV_MCAST_HAVE_MC_PTYPE_CAPA;INIT_HLIST_NODE(&orig_node->mcast_want_all_unsnoopables_node); INIT_HLIST_NODE(&orig_node->mcast_want_all_ipv4_node); INIT_HLIST_NODE(&orig_node->mcast_want_all_ipv6_node); diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index 163cd43c4821..f1061985149f 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -1270,3 +1270,73 @@ int batadv_recv_bcast_packet(struct sk_buff *skb, batadv_orig_node_put(orig_node); return ret; }
+#ifdef CONFIG_BATMAN_ADV_MCAST +/**
- batadv_recv_mcast_packet() - process received batman-adv multicast
packet + * @skb: the received batman-adv multicast packet
- @recv_if: interface that the skb is received on
- Parses the given, received batman-adv multicast packet. Depending on
the + * contents of its TVLV forwards it and/or decapsulates it to hand it to the + * soft interface.
- Return: NET_RX_DROP if the skb is not consumed, NET_RX_SUCCESS
otherwise. + */ +int batadv_recv_mcast_packet(struct sk_buff *skb,
struct batadv_hard_iface *recv_if)+{
struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);struct batadv_mcast_packet *mcast_packet;int hdr_size = sizeof(*mcast_packet);unsigned char *tvlv_buff;int ret = NET_RX_DROP;u16 tvlv_buff_len;if (batadv_check_unicast_packet(bat_priv, skb, hdr_size) < 0)goto free_skb;/* create a copy of the skb, if needed, to modify it. */if (skb_cow(skb, ETH_HLEN) < 0)goto free_skb;/* packet needs to be linearized to access the tvlv content */if (skb_linearize(skb) < 0)goto free_skb;mcast_packet = (struct batadv_mcast_packet *)skb->data;if (mcast_packet->ttl-- < 2)goto free_skb;More of a nit (since we do the same check in broadcasts), but if ttl == 0 on the incoming packet, then we will actually forward it with ttl =255 and that's a bit stupid ...
Mistake on my end on this one, the original value should be used for the comparison so this is okay.
Cheers, Simon