static int gre_rcv(struct sk_buff *skb)
{
struct tnl_ptk_info tpi;
bool csum_err = false;
int hdr_len;
#ifdef CONFIG_NET_IPGRE_BROADCAST
if (ipv4_is_multicast(ip_hdr(skb)->daddr)) {
/* Looped back packet, drop it! */
if (rt_is_output_route(skb_rtable(skb)))
goto drop;
}
#endif
hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), 0);
if (hdr_len < 0)
goto drop;
if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
return 0;
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
drop:
kfree_skb(skb);
return 0;
}
static int gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
{
if (ipgre_rcv(skb, tpi) == PACKET_RCVD)
return 0;
kfree_skb(skb);
return 0;
}
static int gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *unused_tpi)
{
struct tnl_ptk_info tpi;
bool csum_err = false;
int hdr_len;
hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), 0);
if (hdr_len < 0)
goto drop;
if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
tpi.proto == htons(ETH_P_ERSPAN2))) {
if (erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
return 0;
goto drop;
}
if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
return 0;
drop:
kfree_skb(skb);
return 0;
}