net: ethernet: add PTP multicast default MAC address

All except peer delay message in PTP protocol use multicast MAC
address is 01:1b:19:00:00:00

Signed-off-by: Weiwei Guo <guoweiwei@syriusrobotics.com>

include/zephyr/net/ethernet.h

@@ -715,6 +715,22 @@ static inline bool net_eth_is_addr_lldp_multicast(struct net_eth_addr *addr)
  return false;
 }
 
+static inline bool net_eth_is_addr_ptp_multicast(struct net_eth_addr *addr)
+{
+#if defined(CONFIG_NET_GPTP)
+ if (addr->addr[0] == 0x01 &&
+ addr->addr[1] == 0x1b &&
+ addr->addr[2] == 0x19 &&
+ addr->addr[3] == 0x00 &&
+ addr->addr[4] == 0x00 &&
+ addr->addr[5] == 0x00) {
+ return true;
+ }
+#endif
+
+ return false;
+}
+
 const struct net_eth_addr *net_eth_broadcast_addr(void);
 
 /** @endcond */

subsys/net/l2/ethernet/ethernet.c

@@ -302,6 +302,7 @@ static enum net_verdict ethernet_recv(struct net_if *iface,
  !net_eth_is_addr_multicast((struct net_eth_addr *)lladdr->addr) &&
  !net_eth_is_addr_lldp_multicast(
  (struct net_eth_addr *)lladdr->addr) &&
+ !net_eth_is_addr_ptp_multicast((struct net_eth_addr *)lladdr->addr) &&
  !net_linkaddr_cmp(net_if_get_link_addr(iface), lladdr)) {
  /* The ethernet frame is not for me as the link addresses
  * are different.