[LLC]: add multicast support for datagrams

Allow mulitcast reception of datagrams (similar to UDP).
All sockets bound to the same SAP receive a clone.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Stephen Hemminger 2006-05-25 15:10:37 -07:00 committed by David S. Miller
parent 8f182b494f
commit bc0e646796
2 changed files with 55 additions and 8 deletions

View File

@ -79,6 +79,10 @@ static inline int llc_addrany(const struct llc_addr *addr)
return llc_mac_null(addr->mac) && !addr->lsap;
}
static inline int llc_mac_multicast(const u8 *mac)
{
return is_multicast_ether_addr(mac);
}
/**
* llc_mac_match - determines if two mac addresses are the same
* @mac1: First mac address to compare.

View File

@ -282,7 +282,7 @@ static void llc_sap_rcv(struct llc_sap *sap, struct sk_buff *skb)
* mac, and local sap. Returns pointer for socket found, %NULL otherwise.
*/
static struct sock *llc_lookup_dgram(struct llc_sap *sap,
struct llc_addr *laddr)
const struct llc_addr *laddr)
{
struct sock *rc;
struct hlist_node *node;
@ -304,19 +304,62 @@ found:
return rc;
}
/**
* llc_sap_mcast - Deliver multicast PDU's to all matching datagram sockets.
* @sap: SAP
* @laddr: address of local LLC (MAC + SAP)
*
* Search socket list of the SAP and finds connections with same sap.
* Deliver clone to each.
*/
static void llc_sap_mcast(struct llc_sap *sap,
const struct llc_addr *laddr,
struct sk_buff *skb)
{
struct sock *sk;
struct hlist_node *node;
read_lock_bh(&sap->sk_list.lock);
sk_for_each(sk, node, &sap->sk_list.list) {
struct llc_sock *llc = llc_sk(sk);
struct sk_buff *skb1;
if (sk->sk_type != SOCK_DGRAM)
continue;
if (llc->laddr.lsap != laddr->lsap)
continue;
skb1 = skb_clone(skb, GFP_ATOMIC);
if (!skb1)
break;
sock_hold(sk);
skb_set_owner_r(skb1, sk);
llc_sap_rcv(sap, skb1);
sock_put(sk);
}
read_unlock_bh(&sap->sk_list.lock);
}
void llc_sap_handler(struct llc_sap *sap, struct sk_buff *skb)
{
struct llc_addr laddr;
struct sock *sk;
llc_pdu_decode_da(skb, laddr.mac);
llc_pdu_decode_dsap(skb, &laddr.lsap);
sk = llc_lookup_dgram(sap, &laddr);
if (sk) {
skb_set_owner_r(skb, sk);
llc_sap_rcv(sap, skb);
sock_put(sk);
} else
if (llc_mac_multicast(laddr.mac)) {
llc_sap_mcast(sap, &laddr, skb);
kfree_skb(skb);
} else {
struct sock *sk = llc_lookup_dgram(sap, &laddr);
if (sk) {
skb_set_owner_r(skb, sk);
llc_sap_rcv(sap, skb);
sock_put(sk);
} else
kfree_skb(skb);
}
}