Commit 4cd6654b authored by Chaitanya Tata's avatar Chaitanya Tata Committed by Benjamin Cabé
Browse files

net: l2: Add a config option to allow mismatched L3/L2 address packets 

The RFC1122 section 3.3.6 says we SHOULD drop the packets if L2 address
is brodcast but L3 address is unicast, but we had seen some Wi-Fi access
points in the field not conforming to that, and DHCP offer is dropped
due to this and causes Wi-Fi connectivity issues.

As the RFC saus it's SHOULD and not a MUST, add a config option to allow
such packets, disabled by default.

Signed-off-by: default avatarChaitanya Tata <Chaitanya.Tata@nordicsemi.no>
parent 70b6706c

subsys/net/l2/ethernet/Kconfig

+8 −0
Changes for subsys/net/l2/ethernet/Kconfig: 8 added lines, 0 removed lines.
Original line number Diff line number Diff line
@@ -32,6 +32,14 @@ config NET_L2_ETHERNET_MGMT 
	  Enable support net_mgmt Ethernet interface which can be used to

	  configure at run-time Ethernet drivers and L2 settings.





config NET_L2_ETHERNET_ACCEPT_MISMATCH_L3_L2_ADDR

	bool "Accept mismatched L3 and L2 addresses"

	help

	  If enabled, then accept packets where the L3 and L2 addresses do not

	  conform to RFC1122 section 3.3.6. This is useful in dealing with

	  buggy devices that do not follow the RFC.



config NET_VLAN

	bool "Virtual LAN support"

	select NET_L2_VIRTUAL

subsys/net/l2/ethernet/ethernet.c

+4 −0
Changes for subsys/net/l2/ethernet/ethernet.c: 4 added lines, 0 removed lines.
Original line number Diff line number Diff line
@@ -178,6 +178,10 @@ static inline 
enum net_verdict ethernet_check_ipv4_bcast_addr(struct net_pkt *pkt,

						struct net_eth_hdr *hdr)

{

	if (IS_ENABLED(CONFIG_NET_L2_ETHERNET_ACCEPT_MISMATCH_L3_L2_ADDR)) {

		return NET_OK;

	}



	if (net_eth_is_addr_broadcast(&hdr->dst) &&

	    !(net_ipv4_is_addr_mcast((struct in_addr *)NET_IPV4_HDR(pkt)->dst) ||

	      net_ipv4_is_addr_bcast(net_pkt_iface(pkt),

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