/**
* tipc_l2_rcv_msg - handle incoming TIPC message from an interface
* @buf: the received packet
* @dev: the net device that the packet was received on
* @pt: the packet_type structure which was used to register this handler
* @orig_dev: the original receive net device in case the device is a bond
*
* Accept only packets explicitly sent to this node, or broadcast packets;
* ignores packets sent using interface multicast, and traffic sent to other
* nodes (which can happen if interface is running in promiscuous mode).
*/
static int tipc_l2_rcv_msg(struct sk_buff *buf, struct net_device *dev,
struct packet_type *pt, struct net_device *orig_dev)
{
struct tipc_bearer *b_ptr;
if (!net_eq(dev_net(dev), &init_net)) {
kfree_skb(buf);
return NET_RX_DROP;
}
rcu_read_lock();
b_ptr = rcu_dereference(dev->tipc_ptr);
if (likely(b_ptr)) {
if (likely(buf->pkt_type <= PACKET_BROADCAST)) {
buf->next = NULL;
tipc_rcv(buf, b_ptr);
rcu_read_unlock();
return NET_RX_SUCCESS;
}
}
rcu_read_unlock();
kfree_skb(buf);
return NET_RX_DROP;
}
/* tipc_send_msg - enqueue a send request */
static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
struct tipc_bearer *b,
struct tipc_media_addr *dest)
{
int ttl, err = 0;
struct udp_bearer *ub;
struct udp_media_addr *dst = (struct udp_media_addr *)&dest->value;
struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
struct rtable *rt;
if (skb_headroom(skb) < UDP_MIN_HEADROOM) {
err = pskb_expand_head(skb, UDP_MIN_HEADROOM, 0, GFP_ATOMIC);
if (err)
goto tx_error;
}
skb_set_inner_protocol(skb, htons(ETH_P_TIPC));
ub = rcu_dereference_rtnl(b->media_ptr);
if (!ub) {
err = -ENODEV;
goto tx_error;
}
if (dst->proto == htons(ETH_P_IP)) {
struct flowi4 fl = {
.daddr = dst->ipv4.s_addr,
.saddr = src->ipv4.s_addr,
.flowi4_mark = skb->mark,
.flowi4_proto = IPPROTO_UDP
};
rt = ip_route_output_key(net, &fl);
if (IS_ERR(rt)) {
err = PTR_ERR(rt);
goto tx_error;
}
skb->dev = rt->dst.dev;
ttl = ip4_dst_hoplimit(&rt->dst);
udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb, src->ipv4.s_addr,
dst->ipv4.s_addr, 0, ttl, 0, src->port,
dst->port, false, true);
#if IS_ENABLED(CONFIG_IPV6)
} else {
struct dst_entry *ndst;
struct flowi6 fl6 = {
.flowi6_oif = ub->ifindex,
.daddr = dst->ipv6,
.saddr = src->ipv6,
.flowi6_proto = IPPROTO_UDP
};
err = ipv6_stub->ipv6_dst_lookup(net, ub->ubsock->sk, &ndst,
&fl6);
if (err)
goto tx_error;
ttl = ip6_dst_hoplimit(ndst);
err = udp_tunnel6_xmit_skb(ndst, ub->ubsock->sk, skb,
ndst->dev, &src->ipv6,
&dst->ipv6, 0, ttl, 0, src->port,
dst->port, false);
#endif
}
return err;
tx_error:
kfree_skb(skb);
return err;
}
/* tipc_udp_recv - read data from bearer socket */
static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb)
{
struct udp_bearer *ub;
struct tipc_bearer *b;
ub = rcu_dereference_sk_user_data(sk);
if (!ub) {
pr_err_ratelimited("Failed to get UDP bearer reference");
kfree_skb(skb);
return 0;
}
skb_pull(skb, sizeof(struct udphdr));
rcu_read_lock();
b = rcu_dereference_rtnl(ub->bearer);
if (b) {
tipc_rcv(sock_net(sk), skb, b);
rcu_read_unlock();
return 0;
}
rcu_read_unlock();
kfree_skb(skb);
return 0;
}
static int enable_mcast(struct udp_bearer *ub, struct udp_media_addr *remote)
{
int err = 0;
struct ip_mreqn mreqn;
struct sock *sk = ub->ubsock->sk;
if (ntohs(remote->proto) == ETH_P_IP) {
if (!ipv4_is_multicast(remote->ipv4.s_addr))
return 0;
mreqn.imr_multiaddr = remote->ipv4;
mreqn.imr_ifindex = ub->ifindex;
err = ip_mc_join_group(sk, &mreqn);
#if IS_ENABLED(CONFIG_IPV6)
} else {
if (!ipv6_addr_is_multicast(&remote->ipv6))
return 0;
err = ipv6_stub->ipv6_sock_mc_join(sk, ub->ifindex,
&remote->ipv6);
#endif
}
return err;
}
